The Collaborative International Dictionary of English v.0.48:

Quadrate \Quad"rate\, a. [L. quadratus squared, p. p. of
   quadrare to make four-cornered, to make square, to square, to
   fit, suit, from quadrus square, quattuor four. See
   Quadrant, and cf. Quadrat, Quarry an arrow, Square.]
   1. Having four equal sides, the opposite sides parallel, and
      four right angles; square.
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            Figures, some round, some triangle, some quadrate.
                                                  --Foxe.
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   2. Produced by multiplying a number by itself; square. "
      Quadrate and cubical numbers." --Sir T. Browne.
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   3. Square; even; balanced; equal; exact. [Archaic] " A
      quadrate, solid, wise man." --Howell.
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   4. Squared; suited; correspondent. [Archaic] " A generical
      description quadrate to both." --Harvey.
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   Quadrate bone (Anat.), a bone between the base of the lower
      jaw and the skull in most vertebrates below the mammals.
      In reptiles and birds it articulates the lower jaw with
      the skull; in mammals it is represented by the malleus or
      incus.
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