# secant

In trigonometry, secant is the ratio of the length of the hypotenuse (the longest side) 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, that is 1
/ cos *A*.

A secant is also a straight line that meets a curve in two or more points.