正矢

Sine \Sine\, n. [LL. sinus a sine, L. sinus bosom, used in
translating the Ar. jaib, properly, bosom, but probably read
by mistake (the consonants being the same) for an original
j[=i]ba sine, from Skr. j[=i]va bowstring, chord of an arc,
sine.] (Trig.)
(a) The length of a perpendicular drawn from one extremity
of an arc of a circle to the diameter drawn through
the other extremity.
(b) The perpendicular itself. See {Sine of angle}, below.

{Artificial sines}, logarithms of the natural sines, or
logarithmic sines.

{Curve of sines}. See {Sinusoid}.

{Natural sines}, the decimals expressing the values of the
sines, the radius being unity.

{Sine of an angle}, in a circle whose radius is unity, the
sine of the arc that measures the angle; in a right-angled
triangle, the side opposite the given angle divided by the
hypotenuse. See {Trigonometrical function}, under
{Function}.

{Versed sine}, that part of the diameter between the sine and
the arc.


Versed \Versed\, a. [L. versus turned, p. p. vertere. See 1st
{Versed}.] (Math.)
Turned.

{Versed sine}. See under {Sine}, and Illust. of {Functions}.