yeast

nouns

a commercial leavening agent containing yeast cells; used to raise the dough in making bread and for fermenting beer or whiskey
is derived from
any of various single-celled fungi that reproduce asexually by budding or division
is derived from
is a member of
fungi having a zygote or a single cell developing directly into an ascus
is a type of (narrower)
an organism of the kingdom Fungi lacking chlorophyll and feeding on organic matter; ranging from unicellular or multicellular organisms to spore-bearing syncytia