sine
playSimple Definition of sine

geometry : the ratio between the long side (called the hypotenuse) and side that is opposite to an acute angle in a right triangle
Full 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
Learn More about sine

Britannica English: Translation of "sine" for Arabic speakers Britannica.com: Encyclopedia article about "sine"
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