English Reference
noun · verb

yeast

n. · v.
US /ˈjist/ UK /jˈiːst/ yeast UK spelling yeast's, yeast's, yeasting

  1. 01 B2 Upper Intermediate Cooking

    n.a tiny fungus used to make bread rise or to make beer and wine.

    n.a unicellular fungus, specifically of the genus Saccharomyces, used as a leavening agent in baking and a fermenter in brewing.

    Simple

    You need to mix the yeast with warm water and sugar before adding it to the flour.

    In context

    The baker monitored the temperature carefully, as excessive heat would kill the yeast and prevent the dough from rising properly.

    Usage

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

    leavenferment
  2. 02 C1 Advanced Technical Science

    n.a type of very small living thing that is a fungus.

    n.any of various small, single-celled fungi that reproduce by budding or fission.

    Simple

    Scientists study how different types of yeast react to various sugars.

    In context

    The researcher isolated a specific strain of yeast from the skin of the grapes to study its unique fermentation properties.

    fungusmicro organism
  3. 03 C2 Proficiency TechnicalArchaic Science

    v.to bubble and change chemically, like when making beer.

    v.to undergo or cause fermentation; to become frothy through the action of fungi.

    Simple

    The mixture began to yeast as the natural sugars broke down.

    In context

    The liquid was left in the vat to yeast for several days until the desired alcohol content was achieved.

  4. 04 C1 Advanced SlangInformal

    v.to make a story seem bigger or more important than it really is.

    v.to inflate the truth or provide an exaggerated account of an event.

    Simple

    He is always yeasting about how much money he makes at his new job.

    In context

    Don't listen to his version of the story; he tends to yeast whenever he wants to impress a new audience.

    Teacher's tip

    This slang usage is relatively niche and often found in specific regional dialects; learners should use it cautiously.

    understate

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”).

Etymology adapted from Wiktionary, available under CC BY-SA 4.0.

This entry
Origin gem-pro *jestuz
Level B2 · Upper Intermediate
Frequency Frequent
Updated