From The Collaborative International Dictionary of English v.0.48 [gcide]:
Alpenhorn \Al"pen*horn'\, Alphorn \Alp"horn'\, noun [G. Alpenhorn.] A curved wooden horn about three feet long, with a cupped mouthpiece and a bell, used by the Swiss to sound the ranz des vaches and other melodies. Its notes are open harmonics of the tube. [Webster 1913 Suppl.]
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