Geometry - Unit 9 Vocabulary

Bisect

To divide something into two congruent parts

Centroid

The point at which the three medians of a triangle intersect

Circle

The set of all points on a flat surface that are the same distance from a fixed point

Cylinder

A three-dimensional figure that consists of two parallel congruent circular regions (called bases) and a lateral surface containing segments connecting each point on the circular boundary of one base to the corresponding point on the circular boundary of the other

Density

The quantity of something per unit measure, especially length, area, or volume

Incenter

The center of the circle inscribed in a triangle

Line segment

The portion of a line between two points

Median

A line segment that connects a vertex of a triangle with the midpoint of side opposite to the vertex

Net

A diagram that, when folded, forms the surface of a three-dimensional solid

Oblique

A prism that lateral surface(s) are not perpendicular to the base

Perimeter

The distance around the exterior of a figure on a flat surface

Perpendicular bisector

A line segment perpendicular to the original segment, and passing through its midpoint

Polyhedron

A three-dimensional object with no holes that is bounded by polygons

Prism

A three-dimensional figure that consists of two parallel congruent polygons (called bases) and a lateral surface containing segments connecting each point on each side of one base to the corresponding point on the other base

Ratio

Compares two quantities by division

Rhombus

A quadrilateral with four congruent sides

Similar

Two shapes that have exactly the same shape but are not necessarily the same size

Solid

A closed three-dimensional shape and all of its interior points

Surface area

The sum of all the area(s) of the surface(s) of a three-dimensional solid

Three-dimensional

An object that has length, width, and depth

Volume

A measurement of the size of the three-dimensional region enclosed within an object