[1] : The Collaborative International Dictionary of English v.0.48

quadrature \quad"rature\, 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.
      1913 webster

   2. a quadrate; a square. --milton.
      1913 webster

   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.
      1913 webster

   4. astron. the position of one heavenly body in respect to
      another when distant from it 90deg, or a quarter of a
      circle, as the moon when at an equal distance from the
      points of conjunction and opposition.
      1913 webster

   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.
      1913 webster
see also:
quadrate quadrature of the moon quadrature of an orbit 

[2] : WordNet (r) 2.0

quadrature
     n : the construction of a square having the same area as some
         other figure

Quadrature >> Q Words
Quadrature, definition of term: Quadrature
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