The Collaborative International Dictionary of English v.0.48:

Quadrille \Qua*drille"\, n. [F. quadrille, n. fem., fr. Sp.
   cuadrilla meeting of four or more persons or It. quadriglia a
   band of soldiers, a sort of dance; dim. fr. L. quadra a
   square, fr. quattuor four. See Quadrate.]
   1. A dance having five figures, in common time, four couples
      of dancers being in each set.
      [1913 Webster]

   2. The appropriate music for a quadrille.
      [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Quadrille \Qua*drille"\, n. [F. quadrille, n. masc., cf. It.
   quadriglio; or perhaps from the Spanish. See Quadrille a
   dance.]
   A game played by four persons with forty cards, being the
   remainder of an ordinary pack after the tens, nines, and
   eights are discarded. --Hoyle.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Quadrill'e \Qua`dril`l['e]"\, a. [F.] (Art)
   Marked with squares, generally by thin lines crossing at
   right angles and at equal intervals; as, quadrill['e] paper,
   or plotting paper.
   [Webster 1913 Suppl.]

WordNet (r) 3.0 (2006):

quadrille
    n 1: music for dancing the quadrille
    2: a square dance of 5 or more figures for 4 or more couples