leavening

leavening
    n 1: an influence that works subtly to lighten or modify
         something; "his sermons benefited from a leavening of
         humor" [syn: {leaven}, {leavening}]
    2: a substance used to produce fermentation in dough or a liquid
       [syn: {leaven}, {leavening}]
    

Leaven \Leav"en\, v. t. [imp. & p. p. {Leavened}; p. pr. & vb.
   n. {Leavening}.]
   1. To make light by the action of leaven; to cause to
      ferment.
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            A little leaven leaveneth the whole lump. --1 Cor.
                                                  v. 6.
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   2. To imbue; to infect; to vitiate.
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            With these and the like deceivable doctrines, he
            leavens also his prayer.              --Milton.
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Leavening \Leav"en*ing\, n.
   1. The act of making light, or causing to ferment, by means
      of leaven.
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   2. That which leavens or makes light. --Bacon.
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