Dictionary entry

Barm

Webster's Dictionary 1913

Barm (bärm), n. [OE. berme, AS. beorma; akin to Sw. bärma, G. bärme, and prob. L. fermentum. √93.] Foam rising upon beer, or other malt liquors, when fermenting, and used as leaven in making bread and in brewing; yeast. Shak.