Definition of "leaven" []

• An agent, such as yeast, that causes batter or dough to rise, especially by fermentation. (noun)
• An element, influence, or agent that works subtly to lighten, enliven, or modify a whole. (noun)
• To add a rising agent to. (verb-transitive)
• To cause to rise, especially by fermentation. (verb-transitive)
• To pervade with a lightening, enlivening, or modifying influence. (verb-transitive)

American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

• "We are leaven, in heaven. leaven-# a substance used to produce fermentation in dough or a liquid"
• ""_But_," he resumed, with renewed seriousness -- "_But ef Christians on'y knowed it_, dey kin put a _little leaven o 'solid Christianity_ in all de charity flour dey gi'es away, an' hit'll _leaven de whole lot_ so strong dat _too much water can't spile it_, nur _too much fire can't scorch it_, nur _too much fore-sight_ (ur whatever dis heah is de"
• "So "leaven" is used of false doctrine (Mt 16: 12: compare Mt 13: 33)."