余割
Cosecant \Co*se"cant\ (k?-s?"k?nt), n. [For co. secans, an abbrev. of L. complementi secans.] (Trig.) The secant of the complement of an arc or angle. See Illust. of {Functions}.
cosecant n : ratio of the hypotenuse to the opposite side of a right-angled triangle [syn: {cosec}]