Definition of: secant

(sē′kənt, -kant) adjective
Cutting, especially into two parts; intersecting.
—noun
1. Geom. A straight line intersecting a given curve.
2. Trig, a A line drawn from the center of a circle through one extremity of an arc to the tangent drawn from the other extremity of the same arc. b The ratio of this line to the radius of the circle: the reciprocal of the cosine. [<L secans, -antis, ppr. of secare cut]
SECANT
Ratio of ab to ad is the secant of angle a. ab is the secant of arc cd.