co·​tan·​gent (ˌ)kō-ˈtan-jənt How to pronounce cotangent (audio)
: a trigonometric function that for an acute angle is the ratio between the leg adjacent to the angle when it is considered part of a right triangle and the leg opposite
: a trigonometric function cot θ that is equal to the cosine divided by the sine for all real numbers θ for which the sine is not equal to zero and is exactly equal to the cotangent of an angle of measure θ in radians

Word History


New Latin cotangent-, cotangens, from co- + tangent-, tangens tangent

First Known Use

1635, in the meaning defined at sense 1

Time Traveler
The first known use of cotangent was in 1635

Dictionary Entries Near cotangent

Cite this Entry

“Cotangent.” Dictionary, Merriam-Webster, Accessed 3 Dec. 2023.

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