from The American Heritage® Dictionary of the English Language, 4th Edition

  • n. Any of various unicellular fungi of the genus Saccharomyces, especially S. cerevisiae, reproducing by budding and from ascospores and capable of fermenting carbohydrates.
  • n. Any of various similar fungi.
  • n. Froth consisting of yeast cells together with the carbon dioxide they produce in the process of fermentation, present in or added to fruit juices and other substances in the production of alcoholic beverages.
  • n. A powdered or compressed commercial preparation, having yeast cells and inert material such as meal and used chiefly as a leavening agent or as a dietary supplement.
  • n. Foam; froth.
  • n. An agent of ferment or activity: political agitators who are the yeast of revolution.
  • intransitive v. To ferment.
  • intransitive v. To froth or foam.

from Wiktionary, Creative Commons Attribution/Share-Alike License

  • n. An often humid, yellowish froth produced by fermenting malt worts, and used to brew beer, leaven bread, and also used in certain medicines.
  • n. A type of single-celled fungus.
  • n. A compressed cake or dried granules of this substance used for mixing with flour to make bread dough rise.
  • n. A frothy foam.
  • v. To ferment.
  • v. To rise.

from the GNU version of the Collaborative International Dictionary of English

  • n. The foam, or troth (top yeast), or the sediment (bottom yeast), of beer or other in fermentation, which contains the yeast plant or its spores, and under certain conditions produces fermentation in saccharine or farinaceous substances; a preparation used for raising dough for bread or cakes, and making it light and puffy; barm; ferment.
  • n. Spume, or foam, of water.

from The Century Dictionary and Cyclopedia

  • To ferment.
  • n. A yellowish substance, having an acid reaction, produced during the alcoholic fermentation of saccharine fluids, rising partly to the surface in the form of a frothy, flocculent, viscid matter (top or surface yeast), and partly falling to the bottom (bottom or sediment yeast).
  • n. Spumc or foam of water; froth.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

  • n. any of various single-celled fungi that reproduce asexually by budding or division
  • n. a commercial leavening agent containing yeast cells; used to raise the dough in making bread and for fermenting beer or whiskey


from The American Heritage® Dictionary of the English Language, 4th Edition

Middle English yeest, from Old English gist.

from Wiktionary, Creative Commons Attribution/Share-Alike License

From Old English ġiest, from Proto-Germanic *jestuz.


  • Their flavor become more intense and complex with the longer the yeast is allowed to develop.

    Meet Norton

  • Set aside for 5-10 minutes, until the yeast is activated and bubbly.

    Archive 2007-07-01

  • Just let me know what the name of the yeast is and where I might find it.

    Kitchen Forum

  • The microscopic plants which we call yeast are widely distributed in the air, and float around there until chance brings them in contact with a substance favorable to their growth, such as fruit juices and moist warm batter.

    General Science

  • When the fermentation has gone on so long that the yeast begins to look brown, the beer should be tunned; that is, the yeast is removed, and the beer is put into the casks in which it is to remain; and, in general, the beer is not taken down into the cellar till at this period.

    The Lady's Country Companion: or, How to Enjoy a Country Life Rationally

  • All yeast is best purified before it is used; that is, the yeast should be put into a vessel, and, cold spring water being poured upon it, they should be stirred together and then left to settle.

    The Lady's Country Companion: or, How to Enjoy a Country Life Rationally

  • Its scientists have altered a pathway in yeast similar to one in plants and trees that makes smells and flavors.

    Allylix Sniffs Out Biotech For New Fragrances

  • The only time you even hear about yeast is if a winery is using naturally occurring yeasts to ferment a particular wine.


  • Put the yeast and milk in the bowl of a stand mixer and, using a wooden spoon, stir until the yeast is dissolved.

    Archive 2009-04-01

  • But a packet of active dry yeast is roughly 2 1/2 teaspoons: which do you mean, a packet or 1 teaspoon?

    Jalapeno cheese bun recipe for a proper Texas burger | Homesick Texan


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  • Even has a Spoonerism punch line. Cute!

    June 22, 2008

  • This reminds me of the first poem I ever memorized:

    There was an Old Man with a beard,

    Who said, "It is just as I feared! --

    Two Owls and a Hen, four Larks and a Wren,

    Have all built their nests in my beard!

    -E. Lear

    June 22, 2008

  • *laughs*

    Oh, Asa, I like that one!

    (Pro -- it's a play on words, based on the first line of a Rudyard Kipling poem. See here.)

    June 22, 2008

  • *guffaws*

    June 21, 2008

  • (trying to find the joke in the internet to get it)

    ((don't worry I'll find it))

    (((sad because it will lose all its fun anyway)))

    June 21, 2008

  • HA HA HAHA!!!!

    June 21, 2008

  • A farmer was perplexed because birds kept building a nest in his horse's mane. The vet told him to sprinkle yeast in the horse's mane every morning for three days. It worked.

    Surprised, the farmer asked the vet why. He answered that even a schoolchild should have been able to figure it out. "Everyone knows yeast is yeast, and nest is nest, and never the mane shall tweet."

    June 21, 2008