point
It marks a location and is named by a capital letter; it has no thickness and 0 dimension.
line
An infinite set of points that goes on forever; it has no thickness and it is one dimensional.
plane
A flat surface that goes on forever in two directions; an infinite set of points; it has no thickness and is two dimensional.
space
The set of all points. It is three dimensional.
collinear
Points that lie on the same line.
noncollinear
Points that do not lie on the same line.
coplanar
Points that lie on the same plane.
noncoplanar
Points that do not lie on the same plane.
intersection
The set of points both figures have in common.
segment
Part of a line consisting of two end points and all the points between them.
ray
Part of a line that starts at a particular point and extends infinitely in one direction.
perpendicular
Two lines that intersect to form right angles.
parallel
Lines that do not intersect but are in the same plane.
skew
Lines that are not parallel and do not intersect.
opposite rays
Two rays that share a common endpoint but extends in opposite directions and makes a line.
congruent segments
Segments that have the same length.
midpoint
A point that divides a segment into two congruent segments.
endpoint
Marks the end of a line segment or ray.
segment bisector
A line that divides a segment at its midpoint to form two congruent segments.
perpendicular bisector
A line that passes through the midpoint of a segment and is perpendicular to that segment.
intersecting lines
Two lines that cross at a given point.