Basic Geometry Terms

A portion of a line that starts at a point (the endpoint) and continues forever in one direction.

• Point

• Parallel

• Ray

• Line

An undefined term in Geometry. A specific location. It has no dimension and is represented by a dot.

• Line

• Midpoint

• Collinear

• Point

Points that lie on the same line

• Space

• Collinear Points

• Bisector

• Coplanar Points

An undefined term in Geometry. A connected straight path. It has no thickness and it continues forever in both directions.

• Endpoints

• Midpoint

• Line

• Segment Bisector

Points or lines all in one plane.

• Ray

• Collinear

• Point

• Coplanar

The point that divides the segment into two segments that have the same length.

• Coplanar

• Midpoint

• Ray

• Line

A portion of a line consisting of two points (endpoints) and all points between them.

• Line

• Point

• Line Segment

• Collinear Points

Two segments that have the same length.

• Line Segment

• Parallel

• Coplanar

• Congruent Segments

An undefined term in Geometry. A flat surface. It has no thickness and it extends forever in all directions.

• Plane

• Line

• Point

• Ray

Lines in the same plane that do not intersect.

• Bisector

• Collinear

• Coplanar

• Parallel Lines