from The American Heritage® Dictionary of the English Language, 4th Edition
- adj. Full of barm; foamy.
- adj. Eccentric; daft.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- adj. containing barm, i.e. froth from fermented yeast
- adj. dotty, goofy, wacko.
from the GNU version of the Collaborative International Dictionary of English
- adj. Full of barm or froth; in a ferment.
from The Century Dictionary and Cyclopedia
- Containing or resembling barm or yeast; frothy.
- Hence Barmy-brained; empty-headed.
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- adj. informal or slang terms for mentally irregular
- adj. marked by spirited enjoyment
Sense 2, alteration of balmy.(American Heritage® Dictionary of the English Language, Fourth Edition)
From Old English beorma ("yeast") (Wiktionary)
Probably an alteration of balmy (Wiktionary)