# cosecant

[koh-see-kuh nt, -kant]

- (in a right triangle) the ratio of the hypotenuse to the side opposite a given angle.
- the secant of the complement, or the reciprocal of the sine, of a given angle or arc. Abbreviation: csc

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Also cosec.

## Origin of cosecant^{}

Dictionary.com Unabridged
Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

## cosecant

- (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 opposite side; the reciprocal of sineAbbreviation: cosec

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Collins English Dictionary - Complete & Unabridged 2012 Digital Edition
© William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins
Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

## Word Origin and History for cosecant

### n.

1706, from co, short for complement, + secant.

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Online Etymology Dictionary, © 2010 Douglas Harper

## cosecant

[kō-sē′kănt′]

- The ratio of the length of the hypotenuse in a right triangle to the length of the side opposite an acute angle. The cosecant is the inverse of the sine.
- The reciprocal of the ordinate of the endpoint of an arc of a unit circle centered at the origin of a Cartesian coordinate system, the arc being of length x and measured counterclockwise from the point (1, 0) if x is positive or clockwise if x is negative.
- A function of a number x, equal to the cosecant of an angle whose measure in radians is equal to x.

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The American Heritage® Science Dictionary
Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.