\Quad"ra*ture\, n. [L. quadratura: cf. F. quadrature.
See {Quadrate}, a.]
1. (Math.) The act of squaring; the finding of a square
   having the same area as some given curvilinear figure; as,
   the quadrature of a circle; the operation of finding an
   expression for the area of a figure bounded wholly or in
   part by a curved line, as by a curve, two ordinates, and
   the axis of abscissas.
2. A quadrate; a square. --Milton.
3. (Integral Calculus) The integral used in obtaining the
   area bounded by a curve; hence, the definite integral of
   the product of any function of one variable into the
   differential of that variable.
4. (Astron.) The position of one heavenly body in respect to
   another when distant from it 90[deg], or a quarter of a
   circle, as the moon when at an equal distance from the
   points of conjunction and opposition.
{Quadrature of the moon} (Astron.), the position of the moon
   when one half of the disk is illuminated.
{Quadrature of an orbit} (Astron.), a point in an orbit which
   is at either extremity of the latus rectum drawn through
   the empty focus of the orbit.