co·​se·​cant | \ (ˌ)kō-ˈsē-ˌkant How to pronounce cosecant (audio) , -kənt \

Definition of cosecant

1 : a trigonometric function that for an acute angle is the ratio between the hypotenuse of a right triangle of which the angle is considered part and the leg opposite the angle
2 : a trigonometric function csc θ that is the reciprocal of the sine for all real numbers θ for which the sine is not zero and that is exactly equal to the cosecant of an angle of measure θ in radians

First Known Use of cosecant

circa 1706, in the meaning defined at sense 1

History and Etymology for cosecant

New Latin cosecant-, cosecans, from co- + secant-, secans secant

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The first known use of cosecant was circa 1706

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Cite this Entry

“Cosecant.” Dictionary, Merriam-Webster, Accessed 23 Feb. 2020.

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