Definition of leaven:

part of speech: verb

To raise with leaven: to taint.

part of speech: verb

To mix with leaven.

part of speech: noun

Fermenting dough.

part of speech: verb

To produce fermentation in; to make light, as dough; to mix; as, to leaven correction with a little praise.

part of speech: noun

A ferment mixed with a substance to render it light, as yeast with dough; any strong, silent influence.

Usage examples for leaven:

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