ENGLISH
REFERENCE

yeast

n. C / U
B2 Upper Intermediate US //ˈjist// UK //jˈiːst// yeast Slang

n. a tiny living thing that makes bread rise and turns sugar into alcohol. It is used in baking and brewing to create bubbles and flavor.

n. a microscopic, single-celled fungus capable of fermenting carbohydrates into carbon dioxide and ethyl alcohol.


SIMPLE

The baker adds yeast to the dough to make it rise.

CONTEXTUAL

If the water is too hot, it will kill the yeast and the bread will not expand.

COMPLEX

Modern industrial brewing relies on specific strains of yeast to ensure consistent flavor profiles and predictable fermentation times across different batches of beer.

Synonyms
Origin

From Middle English yest, yeest, gest, gist, from Old English ġist, ġyst, from Proto-West Germanic jestu, from Proto-Germanic jestuz. Cognate with Saterland Frisian Jääst (“yeast”), West Frisian gêst, gist (“yeast”), Dutch gist (“yeast”), German Low German Gest (“yeast”), German Gischt (“sea foam”), Swedish jäst (“yeast”), Norwegian jest (“yeast”), Icelandic jöstur (“yeast”).

Usage

Uncountable when referring to the substance generally; countable when referring to specific biological strains or commercial packets.

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