Leaven1. (n.) Yeast or any substance that causes dough to rise, usually by fermentation.
2. (n.) Anything which makes a general assimilating (especially a corrupting) change in the mass.
3. (v. t.) To make light by the action of leaven; to cause to ferment.
4. (v. t.) To imbue; to infect; to vitiate.
Thesaurus Entries
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