TANGENT (2)

Tan″gent, a. [[L. tangens, -entis, p. pr.]] Touching; touching at a single point; specifically (Geom.) meeting a curve or surface at a point and having at that point the same direction as the curve or surface; — said of a straight line, curve, or surface; as, a line tangent to a curve; a curve tangent to a surface; tangent surfaces. Tangent plane (Geom.), a plane which touches a surface in a point or line. — Tangent scale (Gun.), a kind of breech sight for a cannon. — Tangent screw (Mach.), an endless screw; a worm.