a thing that bisects, specifically a ray that bisects an angle.
A line or curve that bisects or divides a line section, position, or other figure into two equal components.
One who, or whatever, bisects; esp. (Geom.) a straight line which bisects an angle.
A line attracted through vertex of a triangle to be able to bisect either the exact opposite part (bisector of side) and/or perspective (bisector associated with direction, or internal bisector), or even bisect the additional angle formed because of the adjacent sides (external bisector).