Definition of perpendicular
- a. - Exactly upright or vertical; pointing to the zenith;
at right angles to the plane of the horizon; extending in a right line
from any point toward the center of the earth.
- a. - At right angles to a given line or surface; as, the
line ad is perpendicular to the line bc.
- n. - A line at right angles to the plane of the horizon;
a vertical line or direction.
- n. - A line or plane falling at right angles on another
line or surface, or making equal angles with it on each side.