barm /ˈbɑrm/
  泡狀酵母
  Barm, n.  The lap or bosom. [Obs.]
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  Barm n.  Foam rising upon beer, or other malt liquors, when fermenting, and used as leaven in making bread and in brewing; yeast.
  barm
       n : a commercial leavening agent containing yeast cells; used to
           raise the dough in making bread and for fermenting beer
           or whiskey [syn: yeast]