1. (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.

abate adjust to agent alter alterant alterative alterer assuage bespread besprinkle box in breathe brew catalyst catalytic agent circumscribe color condition crawl with creep with decoct diffuse diminish dredge dye entincture extend throughout ferment fermentation fill flavor hedge hedge about honeycomb imbrue imbue impregnate infiltrate infuse innovationist innovator instill introducer leave no void leavening limit mitigate moderate modificator modifier modify modulate narrow occupy overrun overspread overswarm palliate penetrate permeate pervade precursor qualify raise reduce regulate by restrain restrict run through saturate season set conditions set limits soften steep suffuse swarm with teem with temper tincture tinge transformer transfuse transmogrifier yeast