sine

noun

ˈsīn How to pronounce sine (audio)
1
: the trigonometric function that for an acute angle is the ratio between the leg opposite the angle when it is considered part of a right triangle and the hypotenuse
2
: a trigonometric function sin θ that for all real numbers θ is exactly equal to the sine of an angle of measure θ in radians and that is given by the sum of the alternating series sinθ=θ−θ33!+θ55!−θ77!+θ99!−…

Examples of sine in a Sentence

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Where previously players could only activate one effect at a time, up to four effects can now sound simultaneously – with users able to choose from chorus, vibrato, flanger, delay (with tap tempo), reverb (acoustic, hall or plate) and tremolo (sine/triangle) out of the box. — Paul Ridden, New Atlas, 7 Oct. 2024 Six hundred years ago, mathematicians were building tables of sines and cosines, which were needed for navigation, but these can now be generated by computers in seconds. — Matteo Wong, The Atlantic, 4 Oct. 2024 Automorphic forms are a generalization of periodic functions like the sine in trigonometry, whose outputs endlessly repeat as inputs grow. — Kevin Hartnett, Quanta Magazine, 12 Oct. 2023 These functions, such as the sine and cosine, are defined using right triangles. — Leila Sloman, Scientific American, 10 Apr. 2023 See All Example Sentences for sine

Word History

Etymology

Medieval Latin sinus, from Latin, curve

First Known Use

1593, in the meaning defined at sense 1

Time Traveler
The first known use of sine was in 1593

Phrases Containing sine

Rhymes for sine

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Browse Nearby Words

sindry
sine
sin-eater
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Cite this Entry

“Sine.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/sine. Accessed 7 Apr. 2025.

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Kids Definition

sine

noun
ˈsīn How to pronounce sine (audio)
: a trigonometric function that for an acute angle in a right triangle is the ratio of the side opposite the angle to the hypotenuse

More from Merriam-Webster on sine

Britannica.com: Encyclopedia article about sine

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