sine
Trigonometry.
(in a right triangle) the ratio of the side opposite a given acute angle to the hypotenuse.
(of an angle) a trigonometric function equal to the ratio of the ordinate of the end point of the arc to the radius vector of this end point, the origin being at the center of the circle on which the arc lies and the initial point of the arc being on the x-axis. Abbreviation: sin
Geometry. (originally) a perpendicular line drawn from one extremity of an arc of a circle to the diameter that passes through its other extremity.
Mathematics. (of a real or complex number x) the function sin x defined by the infinite series x − (x3/3!) + (x5/5!) − + …, where ! denotes factorial.: Compare cosine (def. 2), factorial (def. 1).
Origin of sine
1Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2024
How to use sine in a sentence
His father stood over him in wonder while he filled a sheet of paper with sines, cosines, secants, and such things.
Harper's Round Table, June 4, 1895 | VariousThe interpolations are effected with the aid of a small table containing the logarithms of 72 sines.
William Oughtred | Florian CajoriAlthough the ratio of the sines is constant, the refractive index varies in different media.
An Elementary Text-book of the Microscope | John William GriffithMinutes of an Hour, are set down according to the same Proportions of Sines before suggested.
A second developed a trigonometry of sines to replace the Ptolemaic trigonometry of chords.
An Introduction to the History of Science | Walter Libby
British Dictionary definitions for sine (1 of 2)
/ (saɪn) /
: Abbreviation: sin
a trigonometric function that in a right-angled triangle is the ratio of the length of the opposite side to that of the hypotenuse
a function that in a circle centred at the origin of a Cartesian coordinate system is the ratio of the ordinate of a point on the circumference to the radius of the circle
Origin of sine
1British Dictionary definitions for sine (2 of 2)
/ (ˈsaɪnɪ) /
(esp in Latin phrases or legal terms) lacking; without
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
Scientific definitions for sine
[ sīn ]
The ratio of the length of the side opposite an acute angle in a right triangle to the length of the hypotenuse.
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 sine of an angle whose measure in radians is equal to x.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
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