yeast

noun \ ˈyēst , especially Southern and Midland US ˈēst \

|Updated on: 9 Aug 2018

Definition of yeast

1 a : 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

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yeast-like

or less commonly yeastlike play \ˈyēst-ˌlīk, especially Southern and Midland US ˈēst-\ adjective

See yeast defined for English-language learners

See yeast defined for kids

Examples of yeast in a Sentence

taxation without representation proved to be the yeast of rebellion

Recent Examples of yeast from the Web

The fast-food coffee chain’s newest snack is made from croissant-style doughnut dough and tossed in cinnamon sugar, which differs from the traditional yeast ring and cake-like doughnut dough.

— alexa imani spencer, USA TODAY, "Doughnuts in stick form: Dunkin' debuts Donut Fries," 27 June 2018
And The People’s Pharmacy discusses lowering cholesterol with red yeast rice, and the uses of gentian violet for fingers and toenails.

— morning brief, The Seattle Times, "Monday Morning Brief, June 11: Summit with North Korea, who Seattle’s newcomers are," 11 June 2018
Similar to the minis, the sliders are served on their yeast rolls and topped with honey butter spread.

— ana calderone, PEOPLE.com, "Chick-fil-A Is Testing Out a New Sandwich That's a Hybrid of Two of Their Classics," 31 May 2018
Homebrew Party bests Gabriel’s in selection of hops and yeast varieties, though Gabriel’s again comes out ahead on pricing.

— markus haas, San Antonio Express-News, "Homebrewers: How to get the best supply prices and selection," 17 May 2018
The Braided Bread Workshop (10 a.m.-noon Saturday) offers instruction on making high-ratio yeast dough, bread braiding and more.

— susan selasky, Detroit Free Press, "Hit these cooking classes to improve your kitchen skills," 16 May 2018
Not only is there a clear separation between fans who either love or loathe the Serbian, but his playing style - tough, unpleasant to the eye but providing the pleasant aftertaste of a goal or two - is eerily reminiscent of the yeast spread.

— SI.com, "Newcastle Looking to Sell Divisive Forward This Summer With Promotion Chasers Fulham Interested," 6 May 2018
Happy Brewing owner Gabe Soukup worked in yeast fermentation at Eli Lilly and Co. His business partner Dave Bellar is a brewer and certified beer judge.

— liz biro, Indianapolis Star, "Double 8 grocery stores: Here's what they are now," 1 May 2018
The celebratory suds are made with hops grown at Hallowed Hops Farm in Lewistown, saison yeast cultured at Omega Yeast Labs in Chicago and grains familiar to Illinois farmers — corn, wheat, oats and barley.

— lori rackl, chicagotribune.com, "Bicentennial bucket list: 20 essential Illinois drinks," 29 June 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'yeast.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

Origin and Etymology of yeast

Middle English yest, from Old English gist; akin to Old High German jesen, gesen to ferment, Greek zein to boil

NEW! Time Traveler

First Known Use: before 12th century

in the meaning defined at sense 1a

See Words from the same year

yeast Synonyms

Phrases

shot in the arm;

Other Food Terms

Reuben, calamari, chuck, curry, edamame, foie gras, hummus, leaven, nonpareil, peel

yeast

verb

Definition of yeast

yeasted; yeasting; yeasts

intransitive verb

: ferment, froth

Recent Examples of yeast from the Web

Same for dozens of styles of fish stew, yeasted rolls, cakes, and pies found around the world.

— National Geographic, "The Secret History of the World's Priciest Spice," 3 May 2017

First Known Use of yeast

1819

in the meaning defined above

See Words from the same year

NEW! Time Traveler

Other Biochemistry Terms

bile, biodegradable, capsaicin, keratin, metabolism

YEAST Defined for English Language Learners

yeast

noun

Definition of yeast for English Language Learners

: a type of fungus that is used in making alcoholic drinks (such as beer and wine) and in baking to help make dough rise

YEAST Defined for Kids

yeast

noun \ ˈyēst \

Definition of yeast for Students

1 : a single-celled fungus that ferments sugar to produce alcohol and carbon dioxide

2 : a commercial product containing living yeast cells that is used in baking to make dough rise and in the making of alcoholic beverages (as wine)

Medical Dictionary

yeast

noun \ ˈyēst \

medical Definition of yeast

1 : a unicellular chiefly ascomycetous fungus (as of the family Saccharomycetaceae) that has usually little or no mycelium, that typically reproduces asexually by budding, and that includes forms (as Saccharomyces cerevisiae) which cause alcoholic fermentation and are used especially in the making of alcoholic beverages and leavened bread

2 : a yellowish surface froth or sediment that occurs especially in sugary fermenting liquids (as fruit juices) and consists chiefly of yeast cells and carbon dioxide

3 : a commercial product containing yeast cells in a moist or dry medium

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