Geometry Terms

Front

Points that lie on the same line

Back

Collinear points

Front

An angle with measure equal to 180°

Back

Straight angle

Front

One dimensional and extends without end in two directions

Back

Line

Front

Part of a line that consists of two points, called endpoints

Back

Line segment

Front

A point that divides, or bisects, a segment into two congruent segments

Back

Midpoint

Front

A flat surface that extends infinitely in all directions

Back

Plane

Front

An angle that measures less than 90°

Back

Acute angle

Front

An angle that measures exactly 90°

Back

Right angle

Front

An angle that measures more than 90° but less than 180°

Back

Obtuse angle

Front

Two angles whose measures add up to 180°

Back

Supplementary angles