- (v.t.) To make light by the action of leaven; to cause to ferment.
- (n.) Any substance that produces or is designed to produce, fermentation, as in dough or liquids; especially, a portion of fermenting dough, which, mixed with a larger quantity of dough, produces a general change in the mass, and renders it light; yeast; barm.
- (n.) Anything which makes a general assimilating (especially a corrupting) change in the mass.
- (v.t.) To imbue; to infect; to vitiate.
Webster's Revised Unabridged Dictionary
| APA | Webster's. (2011). leaven. Retrieved September 26, 2026, from http://smartdefine.org/leaven/definitions/2027127 |
| Chicago | Webster's. 2011. "leaven" http://smartdefine.org/leaven/definitions/2027127 (accessed September 26, 2026). |
| Harvard | Webster's 2011, leaven, Smart Define, viewed 26 September, 2026, <http://smartdefine.org/leaven/definitions/2027127>. |
| MLA | Webster's. "leaven" 27 May 2011. Web. 26 September 2026. <http://smartdefine.org/leaven/definitions/2027127> |