Barm
Barm (barm) , noun
[Old English berme, Anglo-Saxon beorma; akin to Swedish barma, German barme, and prob. Latin fermentum. r93.]
Foam rising upon beer, or other malt liquors, when fermenting, and used as leaven in making bread and in brewing; yeast. — Shakespeare
Barm , noun
[Old English bearm, berm, barm, Anglo-Saxon bearm; akin to English bear to support.]
The lap or bosom. [Obsolete] — Chaucer