Definition of yeast
(Entry 1 of 2)
1a
: a yellowish surface froth or sediment that occurs especially in saccharine liquids (such as fruit juices) in which it promotes alcoholic fermentation, consists largely of cells of a fungus (such as the saccharomyces, Saccharomyces cerevisiae), and is used especially in the making of alcoholic liquors and as a leaven in baking
b
: a commercial product containing yeast fungi in a moist or dry medium
c(1)
: a unicellular fungus that is present and functionally active in yeast, usually has little or no mycelium, and reproduces by budding
(2)
: any of various similar fungi
2
archaic
: the foam or spume of waves
3
: something that causes ferment or activity
were all seething with the yeast of revolt— J. F. Dobie
yeast
verb
yeasted; yeasting; yeasts
Definition of yeast (Entry 2 of 2)
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Merriam-Webster unabridged
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Time Traveler for yeast
The first known use of yeast was before the 12th century
See more words from the same century