noun
sine
syn
noun
1
In trigonometry, a function of an angle giving the ratio of the length of the opposite side to the hypotenuse in a right triangle.
"The sine of 90 degrees is 1."
How to Use Sine
Learner’s notesIn plain EnglishA trigonometric function used to relate angles to the sides of a right triangle.
Common pairings
sine wave
sine function
sine curve
Word Forms
sines plural
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The _____ of 90 degrees is 1.
Etymology
From Latin sinus ("curve, fold, bosom"), which was actually a mistranslation — Arabic mathematicians used a word meaning "sine" that looked, unvowelled, like their word for "bosom," and Latin translators picked the wrong meaning.