Meaning

adjective marked by spirited enjoyment

adjective informal or slang terms for mentally irregular

originFrom barm (“foam rising upon beer or other malt liquors when fermenting, and used as leaven”) + -y (suffix meaning ‘having the quality of’ forming adjectives). Barm is derived from Middle English berm, berme (“foam rising upon ale or beer fermenting; leaven, yeast; foam or head of beer produced by pouring”) [and other forms], from Old English beorma (“foam or head of beer; leaven, yeast”), from…

Etymology from Wiktionary, CC BY-SA 3.0