Source : Webster's Revised Unabridged Dictionary (1913)

Embouchure \Em`bou`chure"\, n. [F., fr. emboucher to put to the
   mouth; pref. em- (L. in) + bouche the mouth. Cf. {Embouge},
   {Debouch}.]
   1. The mouth of a river; also, the mouth of a cannon.

   2. (Mus.)
      (a) The mouthpiece of a wind instrument.
      (b) The shaping of the lips to the mouthpiece; as, a flute
          player has a good embouchure.

Source : WordNet®

embouchure
     n : the aperture of a wind instrument into which the player
         blows directly [syn: {mouthpiece}]