Quantcast
Merriam-Webster Logo
  • Dictionary
  • Thesaurus
  • Medical
  • Scrabble
  • Spanish Central
  • Learner's Dictionary

Medical Dictionary

yeast

play
noun \ˈyēst\

Medical Definition of yeast

  1. 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. 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. 3:  a commercial product containing yeast cells in a moist or dry medium

  4. yeast·like \-ˌlīk\play adjective





Seen and Heard

What made you want to look up yeast? Please tell us where you read or heard it (including the quote, if possible).

WORD OF THE DAY

February 9, 2016

marked by high spirits and laughter

Get Word of the Day daily email!

WORD GAMES

Take a 3-minute break and test your skills!

image1037863653

Which of the following refers to thin, bending ice, or to the act of running over such ice?

spindrift kittly-benders duvet pince-nez
Name That Thing

10 quick questions: hear them, spell them, and see how your skills compare to the crowd.

TAKE THE QUIZ
SCRABBLE® Sprint

Test Your Knowledge - and learn some interesting things along the way.

TAKE THE QUIZ