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leaven

[lev-uh n]
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noun

a substance, as yeast or baking powder, that causes fermentation and expansion of dough or batter.
fermented dough reserved for producing fermentation in a new batch of dough.
an element that produces an altering or transforming influence.

verb (used with object)

to add leaven to (dough or batter) and cause to rise.
to permeate with an altering or transforming element.

Origin of leaven

1300–50; Middle English levain < Anglo-French, Old French levain < Vulgar Latin *levāmen, equivalent to Latin levā(re) to raise + -men deverbal noun suffix (probably not continuous with Latin levāmen means of alleviating, solace)
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Related Words for leaven

lighten, infuse, imbue, raise, affect, cause, change, ferment, activate, catalyze, pepsinate

Examples from the Web for leaven

Contemporary Examples of leaven

Historical Examples of leaven

  • He compares it to little things, to a tiny seed, to a handful of leaven, to a pearl.

    De Profundis

    Oscar Wilde

  • I could feel the leaven working in his soul, you understand.

    Under Western Eyes

    Joseph Conrad

  • It is hard to say if there might not have been some leaven of "pique" in these reasonings.

  • One can hardly conceive how disagreeable this leaven was to the taste.

    Perils and Captivity

    Charlotte-Adlade [ne Picard] Dard

  • The leaven of the psychology of independence was getting in its work.

British Dictionary definitions for leaven

leaven

noun Also: leavening

any substance that produces fermentation in dough or batter, such as yeast, and causes it to rise
a piece of such a substance kept to ferment a new batch of dough
an agency or influence that produces a gradual change

verb (tr)

to cause fermentation in (dough or batter)
to pervade, causing a gradual change, esp with some moderating or enlivening influence

Word Origin for leaven

C14: via Old French ultimately from Latin levāmen relief, (hence, raising agent, leaven), from levāre to raise
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
Word Origin and History for leaven
n.

mid-14c., from Old French levain "leaven, sourdough" (12c.), from Latin levamen "alleviation, mitigation," but used in Vulgar Latin in its literal sense of "a means of lifting, something that raises," from levare "to raise" (see lever). Figurative use from late 14c.

v.

c.1400, from leaven (n.). Related: Leavened; leavening.

Online Etymology Dictionary, © 2010 Douglas Harper