Perpendicular

(pür-pěn-dik'u-lar.) [From L. perpendicular is,hanging straight down.] Hanging or extending in a right line from any point towards the centre of the earth or of gravity, and therefore at right angles with the plane of the horizon.-(Geom.) A line making two equal angles, called right angles, with the line which it intersects vertically. [s. 698]