from The American Heritage® Dictionary of the English Language, 4th Edition
- n. A brass wind instrument, similar to the French horn, often used in military or marching bands.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. A brass instrument frequently used in place of the French horn in marching bands and similar performance groups
mello(w) + -phone.(American Heritage® Dictionary of the English Language, Fourth Edition)