althorn definition by Webster's New World
Webster's New World College Dictionary Copyright © 2010 by Wiley Publishing, Inc., Cleveland, Ohio. Used by arrangement with John Wiley & Sons, Inc.
any of a number of alto or tenor brass instruments, esp. the alto saxhorn
also alto horn
althorn definition by American Heritage Dictionary
Any of several upright, valved brass wind instruments used especially in bands.
Origin: German : alt, alto (from Italian alto; see alto) + Horn, horn; see alpenhorn .