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noun leav·en \ˈle-vən\

Simple Definition of leaven

  • : a substance (such as yeast) that makes dough rise and become light before it is baked

  • : something that makes a situation or mood less serious

Source: Merriam-Webster's Learner's Dictionary

Full Definition of leaven

  1. 1 a :  a substance (as yeast) used to produce fermentation in dough or a liquid; especially :  sourdough b :  a material (as baking powder) used to produce a gas that lightens dough or batter

  2. 2 :  something that modifies or lightens

Examples of leaven in a sentence

  1. a serious book that includes a few humorous stories as leaven

Origin of leaven

Middle English levain, from Anglo-French levein, from Vulgar Latin *levamen, from Latin levare to raise — more at lever

First Known Use: 14th century

Rhymes with leaven



verb, leav·en

Simple Definition of leaven

  • : to make (something) less serious and often more exciting

  • : to add leaven to (bread, dough, etc.)

Source: Merriam-Webster's Learner's Dictionary

Full Definition of leaven

leavenedleavening play \ˈlev-niŋ, ˈle-və-\

  1. transitive verb
  2. 1 :  to raise (as bread) with a leaven

  3. 2 :  to mingle or permeate with some modifying, alleviating, or vivifying element; especially :  lighten <a sermon leavened with humor>

Examples of leaven in a sentence

  1. He needs to leaven his speeches with more humor.

  2. using yeast to leaven the dough

15th Century

First Known Use of leaven

15th century

Synonym Discussion of leaven

infuse, suffuse, imbue, ingrain, inoculate, leaven mean to introduce one thing into another so as to affect it throughout. infuse implies a pouring in of something that gives new life or significance <new members infused enthusiasm into the club>. suffuse implies a spreading through of something that gives an unusual color or quality <a room suffused with light>. imbue implies the introduction of a quality that fills and permeates the whole being <imbue students with intellectual curiosity>. ingrain , used only in the passive or past participle, suggests the deep implanting of a quality or trait <clung to ingrained habits>. inoculate implies an imbuing or implanting with a germinal idea and often suggests stealth or subtlety <an electorate inoculated with dangerous ideas>. leaven implies introducing something that enlivens, tempers, or markedly alters the total quality <a serious play leavened with comic moments>.

LEAVEN Defined for Kids


verb leav·en \ˈle-vən\

Definition of leaven for Students


  1. :  to cause to rise by adding something (as baking powder) that produces a gas <leavened bread>

Learn More about leaven

Seen and Heard

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to manage or play awkwardly

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