sine

[ sahyn ]

noun

1. Trigonometry.
   1. (in a right triangle) the ratio of the side opposite a given acute angle to the hypotenuse.
   2. (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. : sin
2. Geometry. (originally) a perpendicular line drawn from one extremity of an arc of a circle to the diameter that passes through its other extremity.
3. Mathematics. (of a real or complex number x ) the function sin x defined by the infinite series x − ( x 3 /3!) + ( x 5 /5!) − + …, where ! denotes factorial. Compare cosine ( def 2 ), factorial ( def 1 ).

sine

¹

/ ˈsaɪnɪ /

preposition

1. (esp in Latin phrases or legal terms) lacking; without

sine

²

/ saɪn /

noun

1. sin
   1. a trigonometric function that in a right-angled triangle is the ratio of the length of the opposite side to that of the hypotenuse
   2. 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

sine

/ sīn /

1. The ratio of the length of the side opposite an acute angle in a right triangle to the length of the hypotenuse.
2. 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.
3. A function of a number x , equal to the sine of an angle whose measure in radians is equal to x.

Word History and Origins

Origin of sine¹

1585–95; < New Latin, Latin sinus a curve, fold, pocket, translation of Arabic jayb literally, pocket, by folk etymology < Sanskrit jiyā, jyā chord of an arc, literally, bowstring

Word History and Origins

Origin of sine¹

C16: from Latin sinus a bend; in New Latin, sinus was mistaken as a translation of Arabic jiba sine (from Sanskrit jīva, literally: bowstring) because of confusion with Arabic jaib curve

Example Sentences

“I said, ’Cause, man, No. 1: we sculpt an electronic signal into a sine wave that’s smooth, or a sawtooth, which is rough.

From Los Angeles Times

He talks a lot about what you just mentioned, which is the sort of sine curve of public interest in surveillance.

From Salon

What I did in the meantime — because I knew that I had to be there and eat the food, and know the people, and that was sine qua non.

From Los Angeles Times

Impartiality is the sine qua non for any jurist, therefore, the privilege of a lifetime appointment requires strict avoidance of even the slightest appearance of partisanship.

From Salon

But a first hostage deal “is the sine qua non of the administration’s larger regional deal,” said Martin S. Indyk, a former U.S. ambassador to Israel.

From New York Times