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Noun: yeast  yeest
  1. A commercial leavening agent containing yeast cells; used to raise the dough in making bread and for fermenting beer or whiskey
    - barm
  2. Any of various single-celled fungi that reproduce asexually by budding or division

Derived forms: yeasts

Type of: fungus, leaven, leavening

Part of: Endomycetales, order Endomycetales

Encyclopedia: Yeast