sine

(sīn)

noun

the reciprocal of the cosecant; specif.,

the ratio of the opposite side of a given acute angle in a right triangle to the hypotenuse
an equivalent, positive or negative ratio for certain related angles (Ex.: the sine of 57° or 123° is .8387, of 237° or 303° is -.8387) or real numbers representing radians (Ex.: the sine of .9948 radians (57°) is .8387)

Origin: ML sinus (< L, a bend, curve, hanging fold of a toga), used as transl. of Ar jaib, sine, bosom of a garment

without

Origin: L

See sine in American Heritage Dictionary 4

noun Abbr. sin

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.
In a right triangle, the ratio of the length of the side opposite an acute angle to the length of the hypotenuse.

Origin:

Origin: Medieval Latin sinus (mistranslation of Arabic jayb, sine, as if jayb, fold in a garment)

Origin: , from Latin, curve, fold

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