AGS+Geometry+Vocabulary

- an [|angle]
 * m[[image:ANGLE.gif width="42" height="21"]] ****ABC **- the measure of angle ABC

- the symbol for degrees

- see [|composite transformation]

- a 90 degree [|angle]; a [|right angle]

- tick marks show that the corresponding lines are of equal length; any number of ticks can be used to distinguish groups of lines

- a circle

- implies; see [|conditional]

- if and only if; see [|biconditional]

- [|parallel]

- parallel lines

- [|perpendicular]

- [|congruent]  <span style="font-family: 'Times New Roman','serif'; font-size: 16px;"> <span style="font-family: 'Times New Roman','serif'; font-size: 16px;"> <span style="font-family: 'Times New Roman','serif'; font-size: 16px;"> <span style="font-family: 'times new roman','serif'; font-size: 16px; line-height: 0px; overflow: hidden;"> <span style="font-family: 'Times New Roman','serif'; font-size: 16px;"> <span style="font-family: 'times new roman','serif'; font-size: 16px; line-height: 0px; overflow: hidden;"> __** y2-y1 **__ x2-x1 <span style="font-family: 'Times New Roman','serif'; font-size: 16px;"> **<span style="font-family: 'Times New Roman','serif'; font-size: 24px;">[|Back to top] **
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">~ **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- not; see [|inverse], [|contrapositive]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">~ **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- similar; see [|similar figures]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">{ } **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- set markers
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">[[image:PI2.gif]] ( ****<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">*) **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- [|pi]; *for those of you who can't read math tags yet)
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Ø **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- a [|null set]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">A' **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- 'prime'; designates an [|image] corresponding to the [|preimage] using the same variable; see [|reflection]
 * a ****<span style="font-family: 'Times New Roman','serif'; font-size: 16px;"> //E// **** b **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- a <span style="font-family: 'Times New Roman','serif'; font-size: 16px;"> is an element in b
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Acute ****<span style="font-family: 'Times New Roman','serif'; font-size: 16px;"> angle **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- an [|angle] whose measure is greater than 0 but less than 90 degrees; see [|obtuse angle]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Adjacent angles **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- 2 nonstraight and nonzero angles that have a common side in the interior of the angle formed by the noncommon sides
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Algorithm **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- a sequence of steps leading to a desired end
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Alternate exterior angles **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- [|exterior angles] on alternate sides of the [|transversal] (not on the same parallel line)
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Alternate interior angles **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- ditto as above, only with [|interior angles]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Altitude **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- height
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Altitude of a conic solid **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- the length of a segment whose endpoints are the [|vertex] and a point on the [|plane] of the [|base] that is [|perpendicular] to the plane of the base
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Altitude of a cylindric solid **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- the distance between the [|planes] of the [|bases]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Altitude of a trapezoid **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- the distance between the[| bases] of a [|trapeziod]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Altitude of a triangle **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- the [|perpendicular] segment from a [|vertex] to the line containing the opposite side of a [|triangle]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Ambiguous **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- not stable; changing
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Analytic geometry **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- see [|coordinate geometry]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Angle **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- the union of 2 rays that have the same endpoint; measured in degrees or radians (trig.); the five types of angles are [|zero], [|acute], [|right], [|obtuse], and [|straight]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Angle bisector **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- a ray that is in the interior of an angle and forms two equal angles with the sides of that angle
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Angle measure between a line and a plane **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- the smallest of the angles formed when a [|line] intersects a [|plane]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Angle side **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- one of the two rays forming an angle
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Antecedent **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- the 'if' part of a [|conditional]; represented by p <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">; aka **hypothesis**, **given**, **problem**; see [|consequent]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Area **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- the amount of space taken up in a [|plane] by a figure
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Arc **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- a path from one [|node] in a [|network] to another; doesn't have to be straight & can be more than 1 line between 2 nodes; part of a circle; see [|minor arc], [|major arc]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Arc length **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- the distance between an [|arc's] endpoints along the path of the [|circle]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Area( **** F ****<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">) **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- the area of figure F
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Automatic drawer **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- a computer program that lets you build constructions
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Axis **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- the line containing the [|vertex] of a [|conic solid] and the center of the [|base]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Base **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- the side of an [|isoscoles triangle] whose endpoints are the [|vertices] of the base angles
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Base angle **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- the [|angle] opposite one of the [|equilateral] sides in an [|isoscoles triangle]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Base angle of a trapezoid **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- consecutive angles that share a base of a [|trapezoid]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Base of a conic solid **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- the planar [|region] that forms the widest point of a [|conic solid]; often labeled as the 'bottom' of the conic solid, it determines the exact shape of the conic solid
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Base of a cylindric solid **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- the original [|region] and its [|translation] [|image]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Base of a trapezoid **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- the parallel sides of a [|trapezoid]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Biconditional **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- a [|conditional] and its [|converse] where the converse is also true; uses the words //if and only if//; written pq
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Bilateral symmetry **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- see [|reflection symmetry]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Bisector of an angle **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- see [|angle bisector]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Bisector pf a segment **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- any [|plane], [|point] or two-dimensional figure containing the the [|midpoint] of the [|segment] and no other points on that segment
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Box **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- a [|surface] made up of [|rectangles]; a **rectangular parallelpided**
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Capacity **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- see [|volume]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Cartesian plane **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- a [|coordinate plane]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Center of a circle **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- the point that all points in the circle are equidistant from
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Center of a rotation **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- the point where the two intersecting lines of a [|rotation] meet
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Center of gravity **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- the [|mean] of the coordinates of points in a [|figure], whether one, two, or three-dimensional
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Central angle of a circle **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- an [|angle] whose [|vertex] is the [|center] of the[| circle]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Chord of a circle **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- a segment whose endpoints are on a [|circle]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Circle **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- the set of points on a plane at a certain distance ([|radius]) from a certain point ([|center]); a [|polygon] with infinite sides
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Circularity **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- when on a search, circling back to a previous place visited (definition, web site, etc.), usually unhelpful or redundant
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Circumference **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- the [|perimeter] of a [|circle]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Clockwise **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- in [|orientation], the direction in which the points are named when, if traveling along the line, the interior of the polygon is on the right (got all that?); see [|counterclockwise]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Coincidental lines **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- [|lines] that are identical (one and the same)
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Colinear **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- in the same line
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Compass **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- a drawing tool used to draw circles at different radii
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Complementary angles **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- 2 angles whose measures, when added together, equal 90 degrees; see [|supplementary angles]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Composite transformation **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- The composite of a first [|transformation] S <span style="font-family: 'Times New Roman','serif'; font-size: 16px;"> and a second transformation T <span style="font-family: 'Times New Roman','serif'; font-size: 16px;"> is the transformation [|mapping] a point P <span style="font-family: 'Times New Roman','serif'; font-size: 16px;"> onto T <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">( S <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">( P <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">)). When written T2 T1 <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">, do T1 <span style="font-family: 'Times New Roman','serif'; font-size: 16px;"> first; see [|translation], [|rotation], [|glide reflection], [|similarity transformation]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Concave **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- see [|nonconvex]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Concentric circles **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- circles that share the same center, but have different radii
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Conditional **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- a statement that tells if one thing happens, another will follow; written as p[[image:implies.gif width="28" height="24"]]q; see [|antecedent], [|consequent], [|converse], [|inverse], [|contrapositive]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Cone **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- the [|surface] of a [|conic solid] whose [|base] is a [|circle]; see [|right cone]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Congruence tranformation **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- see [|isometry]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Congruent **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- equilateral, equal, exactly the same (size, shape, etc.)
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Congruent figures **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- two figures where one is the [|image] of the other under a [|reflection] or [|composite] of reflections; written AB
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Conic section **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- [|plane section] of a [|cone]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Conic solid **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- the set of points between a point (the [|vertex]) and a non-coplanar [|region] (the [|base]), including the point and the region; see [|cone], [|pyramid], [|regular pyramid], [|right cone]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Conjecture **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- an educated guess or opinion; a hypothesis
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Consecutive sides **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- [|sides] of a [|polygon] that share an endpoint
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Consecutive vertices **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- endpoints of a single [|side] of a [|polygon]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Consequent **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- the 'then' part of a [|conditional]; represented by //q//; aka **conclusion**, **prove**, **answer**
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Constant of an equation **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- the term that has no variable in an equation; example: C
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Construction **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- a precise way of drawing which allows only 2 tools: the [|straightedge] and the [|compass]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Contraction **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- a [|size change] where k <span style="font-family: 'Times New Roman','serif'; font-size: 16px;"> is less than 1
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Contrapositive **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- a type of conditional; if not q, then not p; written ~q[[image:implies.gif width="30" height="26"]]~p; see [|inverse]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Converse **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- a reversed [|conditional]; if a conditional is p[[image:implies.gif width="28" height="24"]]q, than its converse is q[[image:implies.gif width="26" height="23"]]p
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Convex set **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- a set of points in which all segments connecting points of the set lie entirely in the set; There are three things one can do to see if a figure is convex - look for "dents", extend the segments (they shouldn't enter the figure), and connect any two points within the figure with a segment (if any part of the segment lies outside the figure, it's concave); see [|nonconvex set]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Coordinate **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- a number that identifies (or helps to identify) a point on a number line (or on a plane, or in space)
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Coordinate geometry **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- the study of geometrically representing ordered pairs of numbers
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Coordinate plane **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- a plane in which every point is identified with exactly 1 number and vice versa; a two-dimensional graph
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Coordinatized line **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- a line on which every point is identified with exactly 1 number and vice versa; a one-dimensional graph. The distance between 2 parts on a coordinatized line is the absolute value of the difference of their coordinates.
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Coplanar **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- within the same plane
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Corollary to a theorem **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- a [|theorem] that is easily proved from the first
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Corresponding angles **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- any pair of angles in similar locations with respect to a [|transversal]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Coterminal angles **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- two [|angles] that have the same [|terminal side]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Counterclockwise **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- in [|orientation], the direction in which points are named when, if travelling on the line, the interior of the figure is on the left side; see [|clockwise]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Counterexample **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- a situation in a conditional for which the antecedent is true, but the conditional is false; aka **contradiction**
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Cylindric solid **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- the set of points between a [|region] and its [|translation] in [|space], including the region and its [|image]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Cylinder **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- the surface of a cylindric solid whose base is a [|circle]; see [|right cylinder]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Cylindric surface **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- the [|union] of the [|bases] and the [|lateral surface]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Decagon **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- a ten-sided [|polygon]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Degree **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- unit used to measure angles
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Dense line **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- the line that contains the shortest path between two points
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Diagonal **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- a segment in a [|polygon] whose endpoints are 2 nonconsecutive vertices
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Diameter of a circle (or sphere) **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- the [|segment] whose endpoints are points on a [|circle] (or [|sphere]) that contains the [|center] of the circle as its [|midpoint]; the length of that segment
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Dilation **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- see [|size change]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Dilatation **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- see [|size change]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Dimensions **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- the width, length, and height of a plane or space figure
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Direction **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- the way a number goes - positive or negative
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Direction of a translation **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- the compass direction in which a translation goes (duh)
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Discrete Line **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- a line made of dots with space inbetween their centers
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Distance **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- the distance between points **A** and **B** is written as **AB**
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Distance between 2 parallel lines **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- the length of a [|perpendicular] segment between them
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Dodecagon **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- a twelve-sided [|polygon]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Dot **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- a description of a [|point] in which the point has a definite size
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Duodecagon **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- a twelve-sided [|polygon]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Drawing **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- a freehand picture using any tool; see [|construction]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Edge **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- a segment that helps to make up a [|face]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Empty set **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- see [|null set]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Ends of a kite **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- the common vertices of the [|equilateral] sides of a [|kite]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Enneagon **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- a nine-sided [|polygon]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Equianglular **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- having angles of the same measure
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Equidistant **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- the same distance from something
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Equilateral **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- equal in length
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Equilateral triangle **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- a [|triangle] whose sides are equal in length
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Even node **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- a [|node] that has an even number of arcs
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Exclusive or **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- one or the other, but not both
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Existential statement **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- a conditional that uses the word 'same'
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Expansion **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- a [|size change] where k <span style="font-family: 'Times New Roman','serif'; font-size: 16px;"> is greater than 1
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Exterior angles **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- angles outside of two lines cut by a [|transversal]; see [|interior angles]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Exterior of an angle **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- the [|nonconvex] set formed by an angle that measures less than 180 degrees; see[| interior of an angle]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Extremes **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- in the [|proportion][[image:extremes.gif width="38" height="23"]], a <span style="font-family: 'Times New Roman','serif'; font-size: 16px;"> and d <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">; see [|means]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Face **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- a [|polygonal] region of a [|surface]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Family tree **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- [|hierarchy]; tower or pyramid of power or importance
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Figure **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- a set of points
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">45-45-90 triangle **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- an [|isoscoles] [|right] [|triangle]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Fundamental region **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- a region used in a [|tesselation]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Geometric mean **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- the number g <span style="font-family: 'Times New Roman','serif'; font-size: 16px;"> such that for two numbers a <span style="font-family: 'Times New Roman','serif'; font-size: 16px;"> and b <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">, [[image:mean.gif width="33" height="22"]]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Given **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- information assumed to be true in a [|proof]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Glide reflection **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- a type of [|composite transformation] where a figure is [|reflected] and then [|translated] in a parallel direction
 * //<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Goldback's Conjecture //**<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- if **n** is an even number greater than 2, then there are always 2 prime numbers whose sum is **n**
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Grade **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- the tilt of a real-life object in relation to the horizontal, often used to determine how steep a hill is
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Graph theory **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- the mathematics of complicated networks
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Great circle **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- the [|circle] formed by the [|intersection] of a [|sphere] and the [|plane] that contains its [|center] and that divides the sphere into two [|hemispheres]; see [|small circle]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Grid **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- a [|tesselation] of [|congruent] [|squares] sometimes used to measure distance
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Harmonic mean **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- two times the product divided by the sum of the two numbers
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Hemisphere **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- half of a [|sphere]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Heptagon **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- a seven-sided [|polygon]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Hexagon **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- a six-sided [|polygon]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Hidden lines **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- broken lines used to signify lines that normally wouldn't be seen in a drawing
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Hierarchy **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- a chart that shows varying levels of importance
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Horizontal line **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- a line whose slope is zero
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Hypotenuse **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- the side opposite the right angle in a [|right triangle]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Icosahedron **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- a 20-sided [|solid]; each side is in the shape of a triangle
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Identity reflection **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- a [|reflection] where the [|preimage] and the [|image] are the same; see [|reflection symmetry]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Identitiy transformation **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- a [|size change] where k <span style="font-family: 'Times New Roman','serif'; font-size: 16px;"> equals 1
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">IFF **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- if and only if; see [|biconditional]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">If-then statement **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- see [|conditional]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Image **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- the [|reflection] of the [|preimage]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Improper subset **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- a [|subset] that includes the entire parent set; see [|proper subset]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Included angle **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- the [|angle] made by two sides of a [|polygon]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Included side **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- the side between two [|angles] in a [|polygon]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Inclusive or **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- one or the other, or both; and/or
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Infinite **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- uncountable
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Initial side **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- the side that the measurement of an angle starts from; see [|terminal side]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Instance of a sentence **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- a situation where the statement is true
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Interior angles **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- [|angles] between two lines cut by a [|transversal]; see [|exterior angles]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Interior of an angle **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- the [|convex] set formed by an angle that measures less than 180 degrees; see [|exterior of an angle]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Interior of a circle **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- the set of points whose distance from the [|center] of the [|circle] is less than that of the [|radius]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Intersecting planes **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- [|planes] that share a [|line]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Intersection of two sets **** A ****<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">and **** B **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- the set of elements which are in both A <span style="font-family: 'Times New Roman','serif'; font-size: 16px;"> and B <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">; written A[[image:intersection.gif width="9" height="10"]]B
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Inverse **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- a form of [|conditional]; if not p, then not q; written ~p~q
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Irrational number **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- decimal number that never ends, never repeats (Ex: pi)
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Irregular region **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- region whose boundary is not the [|union] of circular arcs or segments
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Isometry **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- a [|transformation] that keeps the same size and shape of a figure but moves it to a new location; see [|reflection], [|rotation], [|translation], [|glide reflection]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Isosceles trapezoid **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- a [|trapezoid] that has a pair of [|equiangular] [|base angles]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Isosceles triangle **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- a [|triangle] with two sides of equal length
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Kite **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- a [|quadrilateral] that has two distinct pairs of consecutive [|equilateral] sides
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">L.A. **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- lateral area
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Lateral area **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- the [|area] of the of a [|solid]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Lateral edge **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- a segment whose endpoints are corresponding points of a [|cylindric solid's] [|bases], or whose endpoints are the [|vertex] of a [|conic solid] and a vertex of its [|base]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Lateral faces **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- the [|faces] of the lateral surface of a [|prism], or a [|face] of a [|pyramid] that is not a [|base]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Lateral surface **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- the [|surface] not included in the [|base(s)]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Lattice points **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- points in the coordinate plane with integer coordinates
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Leg of a right triangle **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- a side of a [|right triangle] that include the 90 degree angle
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Limit **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- the actual area of a region
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Line **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- a two-dimensional object that has no endpoints and continues on forever in a plane; formed of infinite points; the 3 orientations that lines may have are [|horizontal], [|vertical], [|oblique], and [|skew lines]; written [[image:line_ab.gif]]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Linear equation **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- Ax + By + C = 0
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Linear pair **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- 2 supplementary adjacent angles whose noncommon sides form a line
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Linear term of an equation **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- the term with a variable, but no exponent in an equation; example: By <span style="font-family: 'Times New Roman','serif'; font-size: 16px;"> in a linear equation
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Line number **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- numbers on the left side of a computer screen that tell the computer in what order to do instructions in a computer programming language such as BASIC
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Line of reflection **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- the line that is reflected over in a [|reflection]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Line perpendicular to a plane **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- a line [|perpendicular] to every line in the [|plane] that it intersects (or any one of them)
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Lines of sight **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- lines from an eye to what it sees that show perspective and what size to draw it
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Location **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- one of the four main description of a [|point]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Locus **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- the set that satisfies a given condition
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Magnitude **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- the value of a number; its distance from the origin
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Magnitude of a rotation **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- the amount of [|rotation] in degrees
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Magnitude of a translation **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- the distance between any point and its [|image]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Major arc **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- an [|arc] whose endpoints form an[| angle] over 180 degrees with the [|center] of the [|circle]; written [[image:major_arc.gif]] - the extra letter is used to distinguish it from a minor arc; see [|minor arc]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Mapping **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- making a [|transformation]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Matrix **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- arrangement of [|pixels]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Mean **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- average
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Meaning **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- a version of a conditional that defines a term, where the term is in the [|antecedent]; see [|sufficient condition]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Means **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- in the [|proportion][[image:means.gif]], b <span style="font-family: 'Times New Roman','serif'; font-size: 16px;"> and c <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">; see [|extremes]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Measure **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- the amount of openness in an [|angle]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Measure of an arc **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- The measure of [|minor arc] [[image:minor_arc.gif]]or [|major arc][[image:major_arc.gif]] is the measure of its [|central angle].
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Median **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- the segment connecting the vertex of an angle in a triangle to the midpoint of the side opposite it
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Midpoint **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- the point M of [[image:segment.gif]] where AM = AB
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Minor arc **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- an [|arc] whose endpoints form an [|angle] less than 180 degrees with the[| center] of the[| circle]; written[[image:minor_arc.gif]] ; see [|major arc]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Net **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- a 2-D figure that can be folded on its segments or curved on its boundaries to form a [|3-D figure]; see article [|here]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Network **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- a group of [|nodes] and [|arcs]
 * N ****<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">-gon **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- a [|polygon] with n <span style="font-family: 'Times New Roman','serif'; font-size: 16px;"> sides
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Node **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- a description of a [|point] in a [|network] where it is possible for two different segments to share the same endpoints
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Nonagon **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- a nine-sided [|polygon]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Nonconvex set **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- a set of points in which **not** all segments connecting points of the set lie entirely in the set; synonym: concave; see [|convex set]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Non-Euclidean geometry **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- [|solid geometry]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Non-included side **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- the side of a [|triangle] that is not included by 2 given [|angles]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Non-overlapping regions **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- regions that don't share interior points
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Nonperspective drawing **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- a three-dimensional drawing that doesn't use [|perspective]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Null set **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- a set with nothing in it
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Number line **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- a [|coordinatized line]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Oblique prism or cylinder **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- a non-right [|prism] or [|cylinder]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Oblique line **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- a line that has a definite slope not equal to zero
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Obtuse ****<span style="font-family: 'Times New Roman','serif'; font-size: 16px;"> angle **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- an [|angle] whose measure is greater than 90 but less than 180 degrees; see [|acute angle]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Octagon **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- an eight-sided [|polygon]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Odd node **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- a [|node] with an odd number of arcs
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">One-dimensional **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- having length, but no width; examples: a [|line], a [|ray], a [|segment]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Opposite faces **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- [|faces] that lie in [|parallel planes]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Opposite rays **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- two rays with a common endpoint that form a line
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Ordered pair **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- the two numbers that (called coordinates) are used to identify a point in a plane; written (x, y)
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Ordered triple **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- the three numbers (called coordinates) that are used to identify a point in space; written (x, y, z)
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Orientation **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- in an image change, the direction in which the points named go (i.e., how A <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">'s position relates to B <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">'s and B <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">'s relates to C <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">'s); either [|clockwise] or [|counterclockwise] for figures
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Overlapping triangles **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- [|triangles] that share a side or [|angle]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Parallel lines **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- two or more coplanar lines that have no points in common or are identical (eg, the same line)
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Parallelogram **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- a [|quadrilateral] with both pairs of opposite sides [|parallel]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Parallelpiped **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- a [|prism] whose opposite faces are all parallelograms and [|congruent] (in pairs)
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Parallel planes **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- [|planes] that have no points in common
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Pentadecagon **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- a 15-sided [|polygon]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Pentagon **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- a five-sided [|polygon]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Perimeter of a polygon **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- the sum of the lengths of the sides of the [|polygon]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Perpendicular bisector **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- the bisector of a segment perpendicular to it
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Perpendicular lines **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- 2 segments, rays, or lines that form a 90 degree angle
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Perpendicular planes **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- [|planes] in which any two intersecting [|lines], one in each plane, form a [|right angle]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Perspective **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- feeling of depth
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Perspective drawing **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- a drawing in which, in order to show perspective, oblique parallel lines will meet
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Pi **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- written [[image:PI2.gif]](for those of you who can't read math tags yet); the ratio C/D <span style="font-family: 'Times New Roman','serif'; font-size: 16px;"> where C <span style="font-family: 'Times New Roman','serif'; font-size: 16px;"> is the [|circumference] and D <span style="font-family: 'Times New Roman','serif'; font-size: 16px;"> is the [|diameter] of a [|circle]; 3.14159265359
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Pixel **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- small dot of color that makes up computer and TV screens
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Plane **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- a two-dimensional group of points that goes on infinitely in all directions; made up of infinite lines
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Plane figure **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- a set of points that are on a plane
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Plane geometry **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- the study of two-dimensional figures in a plane
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Plane section **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- the [|intersection] of a figure with a [|plane]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Point **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- a zero-dimensional figure; while usually left undefined, has four main representions - the [|dot], the [|node], the [|location], and the [|ordered pair] of numbers
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Polarity of a variable **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- the positivity or negativity of a variable; its [|direction]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Polygon **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- a union of 3 or more segments where each segment intersects 2 other segments, one at each endpoint; "many sided"; see [|reflex polygon]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Polygonal region **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- the [|union] of a polygon and its interior
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Polyhedron **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- a [|three-dimensional] [|surface] which is the [|union] of polygonal regions and has no holes
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Postulate **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- a statement assumed to be true without proof; see [|theorem]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Preimage **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- the original object that is [|reflected]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Prism **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- the [|surface] of a [|cylindric solid] whose [|base] is a [|polygon]; see [|right prism], [|parallelpiped], [|box]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Proof **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- a sequence of justified conclusions used to prove the validity of an [|if-then statement]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Proper subset **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- a [|subset] that doesn't include everything in its parent set; see [|improper subset]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Proportion **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- a statement that two [|ratios] are equal
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Proportional **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- one of four numbers that form a true proportion
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Protracter **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- a tool used to measure angles
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Prove **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- the goal of a proof
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Pyramid **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- the [|surface] of a [|conic solid] whose [|base] is a [|polygon]; see [|regular pyramid]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Pythagorean triple **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- a set of three numbers that can be side lengths of a [|right triangle]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Q.E.D. **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- //"quod erat demonstrandum"// (Latin) This stems from medieval translators' habitual tendency of translating the Greek for "this was to be demonstrated" to the Latin phrase above. This appeared originally at the end of many of Euclid's propositions, signifying that he had proved what he set out to prove.
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Q.E.F. **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- //"quod erat faciendum"// is the latin for "which was to be done" It appears in Latin translations of Euclid's works signifying that he had demonstrated what he had set out to demonstrated.
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Quadrangle **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- a four-sided [|polygon]; see [|quadrilateral]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Quadratic equation **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- Ax 2 + By + C = 0
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Quadratic term of an equation **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- the term Ax 2 <span style="font-family: 'Times New Roman','serif'; font-size: 16px;"> in a quadratic equation
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Quadrilateral **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- a four-sided [|polygon]; see [|rhombus],[| parallelogram], [|square], [|rectangle], [|trapezoid], [|isoscoles trapezoid], [|kite]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">R **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- [|rotation]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">r **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- [|radius]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Radii **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- plural form of radius
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Radius **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- the [|segment] whose endpoints are any point on a [|circle] or [|sphere] and its [|center]; the length of that segment
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Rate **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- a ratio where the quantities are of different kinds; example: 60 //miles// per //hour//
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Ratio **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- a quotient of 2 numbers
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Ratio of similtude **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- the ratio of the length of an [|image] to the length of the [|preimage]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Ray **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- a one-dimensional figure that consists of one endpoint A, one point B, all of the points on[[image:segment.gif]], and all points for which B is between them and A; written [[image:ray_ab.gif]]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Rectangle **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- a [|quadrilateral] whose angles are all right angles
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Rectangular solid **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- the [|union] of a [|box] and its interior
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Reference angle **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- the [|angle] of less than 360 degrees that corresponds to an angle of over 360 degrees; In order to get the reference angle, you must subtract 360 degrees from the given angle until there is less than 360 degrees left.
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Refine **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- to change a [|conjecture] slightly so that it is true
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Reflecting line **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- see [|line of reflection]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Reflection image **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- For a point A <span style="font-family: 'Times New Roman','serif'; font-size: 16px;"> not on the reflecting line, its reflection image is the point B <span style="font-family: 'Times New Roman','serif'; font-size: 16px;"> where the reflecting line is the [|perpendicular bisector] of [[image:segment.gif]]. For a point A <span style="font-family: 'Times New Roman','serif'; font-size: 16px;"> on the reflecting line, its reflection image is itself.
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Reflection image of a figure **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- the set of all of the reflection images of points in the figure
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Reflection notation **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- rm <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">( ABC <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">), which stands for the reflection over line m <span style="font-family: 'Times New Roman','serif'; font-size: 16px;"> of figure ABC
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Reflection-symmetric figure **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- a figure that shows [|reflection symmetry]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Reflection symmetry **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- a characteristic of a figure in which there is a reflection line where its reflection is itself
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Reflex polygon **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- a polygon for which 2 or more of its sides intersect each other
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Region **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- the [|union] of a [|figure] and its interior
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Regular polygon **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- a [|convex] [|polygon] whose [|angles] and sides are all [|congruent]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Regular pyramid **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- a [|pyramid] whose [|base] is a [|regular polygon] and whose [|vertex] forms a segment with the center of the [|polygon] [|perpendicular] to its [|plane]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Resolution **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- the density of [|pixels] in a picture
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Rhombus **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- a [|parallelogram] with four [|equilateral] sides
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Right angle **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- an angle whose measure is 90 degrees
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Right cone **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- a [|cone] whose [|axis] is [|perpendicular] to the [|plane] containing its [|base]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Right cylinder **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- a [|cylinder] whose direction of [|sliding] is [|perpendicular] to the [|plane] of the [|base]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Right prism **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- a [|prism] whose direction of [|sliding] is [|perpendicular] to the [|plane] of the [|base]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Right triangle **<span style="font-family: 'times new roman','serif'; font-size: 16px;">- a [|triangle] that has a 90 degree angle
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Rotation **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- the [|composite] of two [|reflections] over intersecting lines
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">S.A. **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- [|surface area]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Scale factor **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- [|size change] magnitude
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Scalene triangle **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- a [|triangle] with no [|equilateral] sides
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Secant to a circle **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- a line that intersects the [|circle] in two points
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Sector **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- part of a [|circle] containing its [|center] and an [|arc]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Segment **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- aka **line segment**; the set of points consisting of two distinct points and all inbetween them; written [[image:segment.gif]]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Semicircle **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- an [|arc] whose [|central angle] is a [|right angle]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Septagon **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- a seven-sided [|polygon]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Set **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- a collection of objects called elements
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Side ****<span style="font-family: 'Times New Roman','serif'; font-size: 16px;"> of a polygon **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- a single [|segment] from the [|union] that forms a [|polygon]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Similar figures **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- two figures that have a similarity transformation mapping one onto the other; written F <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">~ G
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Similarity transformation **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- a [|transformation] that is the [|composite] of [|size changes] and/or [|reflections]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Size change **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- Let A <span style="font-family: 'Times New Roman','serif'; font-size: 16px;"> be a point and k <span style="font-family: 'Times New Roman','serif'; font-size: 16px;"> be a positive real number. For any point B <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">, let T(B) = B' <span style="font-family: 'Times New Roman','serif'; font-size: 16px;"> be the point on[[image:ray_ab.gif]] with OP' = K*OP <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">. Then S <span style="font-family: 'Times New Roman','serif'; font-size: 16px;"> is the size change with **center** A <span style="font-family: 'Times New Roman','serif'; font-size: 16px;"> and **magnitude** k <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">. See [|transformation].
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Size change factor **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- size change magnitude
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Size transformation **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- see [|size change]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Skew lines **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- non-coplanar [|lines] that don't intersect
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Slant height **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- the length of a lateral edge of a [|conic solid]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Slide **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- see [|translation]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Slope **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- the measure of the tilt of a line; rise over run (i.e., how much the line moves up for every movement to the right). The formula for slope is
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Small circle **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- the [|circle] formed by the [|intersection] of a [|sphere] and a [|plane] that doesn't contain the [|center]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Solid **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- the [|union] of the [|surface] and the region of [|space] enclosed by a 3-D figure; examples: [|conic solid], [|cylindric solid], [|rectangular solid]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Solid geometry **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- the study of figures in three-dimensional space
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Space **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- the set of all possible points; made up of infinite planes
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Sphere **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- the set of points in space equidistant from a certain point
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Square **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- an [|equilateral] and [|equianglular] [|quadrilateral]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Straight angle **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- an [|angle] whose measure is 180 degrees, forming a line with its sides
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Straightedge, unmarked **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- just how it sounds, an unmarked tool used to draw straight lines
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Subroutine **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- a previously known [|algorithm] used in another algorithm
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Subset **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- a set that is part of a larger set
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Sufficient condition **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- a version of a [|conditional] that tells you when you can use the term defined, where the term is in the [|consequent]; a condition that implies a preset conclusion; see [|meaning]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Supplementary ****<span style="font-family: 'Times New Roman','serif'; font-size: 16px;"> angles **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- 2 angles whose measur es, when added together, equal 180 degrees
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Surface **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- the boundary of a [|3-D figure]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Surface area **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- the total [|area] of the surface of a [|solid]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Symmetry diagonal **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- the [|diagonal] that [|perpendicularly bisects] the other and is a symmetry line for the [|kite]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Symmetry line **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- the [|line of reflection] in a [|reflection-symmetric figure]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Terminal side **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- the side that the measurement of an angle ends at
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Tesselate **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- the ability of a region to tessalate
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Tesselation **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- a covering of a plane with [|congruent] copies of the same region with no holes or overlaps
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Tetragon **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- a four-sided [|polygon]; see [|quadrilateral]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Theorem **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- important mathematical statements which can be proven by [|postulates], definitions, and/or previously proved theorems
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Three-dimensional **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- having length, width, and thickness (i.e., [|space])
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">3-D figure **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- a set of points in space; examples: [|box], [|cone], [|cylinder], [|parallelpiped], [|prism], [|pyramid], [|regular pyramid], [|right cone], [|right cylinder], [|right prism], [|sphere],
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Tilt **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- the measure of an angle as compared to a horizontal line; what happens when you kick the pinball machine too hard; see [|grade]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Torus **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- a [|3-D figure] formed by rolling a [|rectangle] into a [|cylinder] and bending the cylinder until its bases meet; a "doughnut"; see [|net]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Transformation **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- a correspondence between two sets of points such that each point in the [|preimage] has a unique [|image] and that each point in the image has exactly one preimage; see [|reflection], [|size change], [|isometry], [|composite]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Transformation notation **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- T <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">( P <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">), which stands for the transformation of P <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">; also Sk <span style="font-family: 'Times New Roman','serif'; font-size: 16px;"> where the transformation S <span style="font-family: 'Times New Roman','serif'; font-size: 16px;"> that maps (x, y) <span style="font-family: 'Times New Roman','serif'; font-size: 16px;"> onto (kx, ky) <span style="font-family: 'Times New Roman','serif'; font-size: 16px;"> and k <span style="font-family: 'Times New Roman','serif'; font-size: 16px;"> is the magnitude of that transformation
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Translation **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- the [|composite] of two [|reflections] over [|parallel] lines; aka **slide**
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Transversal **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- a line that intersects 2 others
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Transversible **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- a network in which all arcs can be traced without going over one more than once
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Trapezoid **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- a [|quadrilateral] that has at least one pair of [|parallel] sides; see [|isoscoles trapezoid]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Triangle **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- a polygon with three sides; see [|equilateral triangle], [|isoscoles triangle], [|right triangle], [|scalene triangle]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Triangulate **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- to divide a polygon into triangles
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Tridecagon **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- a 13-sided [|polygon]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Trigon **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- a three-sided [|polygon]; see [|triangle]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Two-dimensional **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- having both width and length, but no thickness
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Undecagon **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- an eleven-sided [|polygon]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Union ****<span style="font-family: 'Times New Roman','serif'; font-size: 16px;"> of two sets **** A ****<span style="font-family: 'Times New Roman','serif'; font-size: 16px;"> and **** B **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- the set of elements in A <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">, B <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">, or both; written A <span style="font-family: 'Times New Roman','serif'; font-size: 18px;">U B
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Unit cube **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- unit of measuring [|volume]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Universal statement **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- a conditional that uses the words 'all' or 'everything'
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Universe **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- in a Venn diagram, everything that is outside the sets
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Vanishing line **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- the horizon; in a [|drawing] it is at the height of viewer's eye
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Vanishing point **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- the point in space where two parallel lines seem to meet
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Vertex **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- see [|node]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Vertex angle **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- the [|angle] formed by the [|equilateral] sides of an [|isoscoles triangle]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Vertex of an angle **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- the common endpoint of the two rays
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Vertex of a conic solid **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- the point that marks the thinnest part of a [|conic solid]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Vertex of a polygon **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- an endpoint of a [|segment] in a [|polygon]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Vertical angles **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- 2 angles that share a common vertex and whose sides form 2 lines
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Vertical line **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- a line that goes straight up and down, and whose slope is defined as infinite or undefined
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">View **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- a [|drawing] of a side of an object
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Volume **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- the amount of [|space] a [|3-D object] can hold
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Wedge **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- see [|sector]
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Zero angle **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- an [|angle] whose measure is 0. In a zero angle, both the initial and terminal sides are the same.
 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Zero-dimensional **<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">- having no dimension; a [|point]