Geometry. an intersecting line, especially one intersecting a curve at two or more points.

Definition: 2

Trigonometry. (in a right triangle) the ratio of the hypotenuse to the side adjacent to a given angle. (originally) a line from the center of a circle through one extremity of an arc to the tangent from the other extremity. the ratio of the length of this line to that of the radius of the circle; the reciprocal of the cosine of a given angle or arc. Abbreviation: sec.

Definition: 3

cutting or intersecting, as one line or surface in relation to another.

Definition: 4

(of an angle) a trigonometric function that in a right-angled triangle is the ratio of the length of the hypotenuse to that of the adjacent side; the reciprocal of cosine sec