sine

sine

noun \ˈsīn\

Definition of SINE

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

Origin of SINE

Medieval Latin sinus, from Latin, curve

First Known Use: 1593