From The Collaborative International Dictionary of English v.0.48 :
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.
[1913 Webster]
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.
[1913 Webster]
From WordNet (r) 3.0 (2006) :
embouchure
n 1: the aperture of a wind instrument into which the player
blows directly [syn: mouthpiece, embouchure]