Definition of yeast
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 bakingb : a commercial product containing yeast fungi in a moist or dry mediumc (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–likeor less commonly
yeastlikeplay \ˈyēst-ˌlīk, especially Southern and Midland US ˈēst-\ adjective
Examples of yeast in a Sentence
taxation without representation proved to be the yeast of rebellion
Recent Examples of yeast from the Web
Kefir is another way of fermenting milk that has more probiotics (beneficial microbes) than yogurt, often carrying twice as many bacterial strains along with some beneficial yeast strains.
In a small bowl, stir together milk and yeast; let stand until slightly foamy, about 5 minutes.
Hops, one of beer’s primary ingredients (along with malt, water, and yeast), are the blossoms of the Humulus lupulus plant.
This year, the festival will feature single yeast strain B45 Gnome.
Sprinkle the yeast over the milk and add the water; let the mixture sit for about 15 minutes.
The specialty clinic diagnoses and treats sexually transmitted diseases including syphilis, gonorrhea, chlamydia, yeast and herpes.
The proliferation of Belgian IPAs ensued, but few could nail the delicate balance of subtle flavors generated by Belgian yeast strains and the hammer of American hops.
Foreign visitors who used to disparage local cooking with the old Woody Allen line about mashed yeast can now tell you what might be on a pizza at Gjelina and ask nervously about the weekly schedule for the Kogi truck.
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
First Known Use: before 12th centurySee Words from the same year
First Known Use of yeast
YEAST Defined for English Language Learners
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
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 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
Seen and Heard
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