Geometry Vocabulary: Lines & Angles

Front

Two straight lines that are always the same distance apart and never touch or cross each other.

Back

Parallel Lines

Front

Lines that intersect (cross) each other at a 90-degree angle, forming right angles.

Back

Perpendicular Lines

Front

Lines that cross each other.

Back

Intersecting Lines

Front

A dot, exact location.

Back

Point

Front

A part of a line between two endpoints.

Back

Line Segment

Front

A line with one endpoint.

Back

Ray

Front

A line that has no end, going in both directions.

Back

Line

Front

An angle less than 90 degrees.

Back

Acute Angle

Front

An angle greater than 90 degrees.

Back

Obtuse Angle

Front

An angle that is 90 degrees.

Back