trigonometric function


: a function (such as the sine, cosine, tangent, cotangent, secant, or cosecant) of an arc or angle most simply expressed in terms of the ratios of pairs of sides of a right-angled triangle

called also circular function

: the inverse (such as the arcsine, arccosine, or arctangent) of a trigonometric function

Example Sentences

Recent Examples on the Web Spacecraft software demands sophisticated mathematical programming, full of matrix operations, trigonometric functions, and multiple precision variables. Frank O’brien, Ars Technica, 30 Jan. 2020

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'trigonometric function.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

Word History

First Known Use

1909, in the meaning defined at sense 1

Time Traveler
The first known use of trigonometric function was in 1909

Dictionary Entries Near trigonometric function

Cite this Entry

“Trigonometric function.” Dictionary, Merriam-Webster, Accessed 5 Dec. 2022.

Kids Definition

trigonometric function


: any of a group of functions (as the sine, cosine, and tangent) that for an acute angle are most easily expressed as ratios between the sides of a right triangle containing the angle

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