# Secant definition

- The ratio of the hypotenuse to the adjacent side of a given acute angle in a right triangle.
- An equivalent, positive or negative ratio for certain related angles (Ex.: the secant of 57° or 303° is 1.8362, of 123° or 237° is −1.8362) or real numbers representing radians (Ex.: the secant of .9948 radians (57°) is 1.8362)

*x*and measured counterclockwise from the point (1, 0) if

*x*is positive or clockwise if

*x*is negative.

*x,*equal to the secant of an angle whose measure in radians is equal to

*x.*