noun Trigonometry. 1.(in a right triangle) the ratio of the side adjacent to a given angle to the side opposite.
2.the tangent of the complement, or the reciprocal of the tangent, of a given angle or arc. Abbreviation: cot, ctn
Origin: 1625–35; <
Neo-Latin cotangent- (stem of
cotangēns). See
co-,
tangent Related forms