###
Acute Triangle

a triangle whose interior angles are all acute

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Angle

the space between two lines or planes that intersect

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Area

the extent of a 2-dimensional surface enclosed within a boundary

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Axis

a straight line through a body or figure that satisfies certain conditions

###
Chamfer

two surfaces meeting at an angle different from 90 degrees

###
Circle

ellipse in which the two axes are of equal length

###
Circumscribe

to draw a geometric figure around another figure so that the two are in contact but do not intersect

###
Countersink

a hole (usually in wood) with the top part enlarged so that a screw or bolt will fit into it and lie below the surface

###
Counterbore

(1) A hole consisting of two depths so that the top of the head of an inserted bolt or screw will be flush with the outside surface. (2) A bit for enlarging the upper part of a hole.

###
Cylinder

a surface generated by rotating a parallel line around a fixed line

###
Diameter

the length of a straight line passing through the center of a circle and connecting two points on the circumference

###
Ellipse

A regular oval shape, traced by a point moving in a plane so that the sum of its distances from two other points is constant, or resulting when a cone is cut by an oblique plane which does not intersect the base.

###
Extrusion

A modeling process that creates a three-dimensional form by defining a closed two-dimensional shape and a length.

###
Inscribe

draw within a figure so as to touch in as many places as possible

###
Mass

a body of matter without definite shape

###
Origin

the point (0,0) where the x-axis and the y-axis intersect in a coordinate plane

###
Parallelogram

a quadrilateral whose opposite sides are both parallel and equal in length

###
Pattern

a customary way of operation or behavior

###
Pi

The numerical value of the ratio of the circumference of a circle to its diameter of approximately 3.14159.

###
Plane

a level of existence or development

###
Polygon

a closed plane figure bounded by straight sides

###
Prism

a polyhedron with two congruent and parallel faces (the bases) and whose lateral faces are parallelograms

###
Quadrilateral

a four-sided polygon

###
Radius

the length of a line segment between the center and circumference of a circle or sphere

###
Rectangle

a parallelogram with four right angles

###
Regular Polygon

a polygon with all sides and all angles equal

###
Revolution

a single complete turn (axial or orbital)

###
Right Triangle

a triangle with one right angle

###
Rotation

the act of rotating as if on an axis

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Round

any circular or rotating mechanism

###
Solid

of definite shape and volume

###
Solid Modeling

A type of 3D CAD modeling that represents the volume of an object, not just its lines and surfaces. This allows for analysis of the object's mass properties.

###
Space

the unlimited expanse in which everything is located

###
Square

(geometry) a plane rectangle with four equal sides and four right angles

###
Surface Area

the extent of a 2-dimensional surface enclosed within a boundary

###
Tap

cut a female screw thread with a tap

###
Taper

the property possessed by a shape that narrows toward a point (as a wedge or cone)

###
Triangle

a three-sided polygon

###
Vertex

the point of intersection of lines or the point opposite the base of a figure

###
Volume

physical objects consisting of a number of pages bound together

###
Cartesian Coordinate System

a coordinate system for which the coordinates of a point are its distances from a set perpendicular lines that intersect at the origin of the system

###
Computer-Aided Design

Software that allows you to create engineering, architectural, and scientific designs

###
Geometric Constraint

Constant, non-numerical relationships between the parts of a geometric figure. Examples include parallelism, perpendicularity, and concentricity.

###
Numeric Constraint

A number value, or algebraic equation that is used to control the size or location of a geometric figure.

###
Obtuse Triangle

a triangle that contains an obtuse interior angle

###
Three-Dimensional

Having the dimensions of height, width, and depth.

###
Two-Dimensional

Having the dimensions of height and width, height and depth, or width and depth only.

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