1a substance, typically yeast, that is added to dough to make it ferment and rise.
dough that is reserved from an earlier batch in order to start a later one fermenting.
2a pervasive influence that modifies something or transforms it for the better:they acted as an intellectual leaven to the warriors who dominated the city
ზმნა
Universal
1 (usually as adjective leavened) cause (dough or bread) to ferment and rise by adding leaven:leavened breads are forbidden during Passover
2permeate and modify or transform (something) for the better:the proceedings should be leavened by humour (as noun leavening)companies of Territorial Army volunteers with a leavening of regular soldiers