se·cant / ˈsēˌkant; -kənt/ • n. 1. (abbr.: sec) Math. the ratio of the hypotenuse to the shorter side adjacent to an acute angle (in a right-angled triangle); the reciprocal of a cosine.2. Geom. a straight line that cuts a curve in two or more parts.

secant In trigonometry, ratio of the length of the hypotenuse to the length of the side adjacent to an acute angle in a right-angled triangle. The secant of angle A is usually abbreviated to sec A, and is equal to the reciprocal of its cosine.

secant in full s. line. XVI. — F. sécant adj., sécante sb. — modL. use of L. secāns, -ant-, prp. of secāre cut; see SECTION, -ANT.