名詞 leaven:

1. a substance used to produce fermentation in dough or a liquid
   同義詞：leavening
2. an influence that works subtly to lighten or modify something
   同義詞：leavening

動詞 leaven:

1. cause to puff up with a leaven
   同義詞：raise, prove

1. "Know ye that a little leaven leaven the whole lump?"
   豈不知小小的一點酵，足以使整團面粉發(fā)起來嗎？
2. Made light and high by yeast or other leaven.
   發(fā)酵的用酵母或其它發(fā)酵劑使 ... 輕而高
3. We often use leaven when baking breads.
   烤面包時，我們經(jīng)常使用發(fā)酵劑。
4. I like his serious style leavened with wit.
   我喜歡他的帶點詼諧的嚴肅文體。

leav.en

n.（名詞）
An agent, such as yeast, that causes batter or dough to rise, especially by fermentation.
酵素：一種可使面粉糊或面團發(fā)大的制劑，尤指通過發(fā)酵，如酵母菌
An element, influence, or agent that works subtly to lighten, enliven, or modify a whole.See Synonyms at catalyst
要素：可微妙地使整體變輕、變活潑或改變的因素、影響力或制劑參見 catalyst
v.tr.（及物動詞）
leav.ened,leav.en.ing,leav.ens
To add a rising agent to.
向…中加發(fā)酵劑
To cause to rise, especially by fermentation.
使膨脹，尤指通過發(fā)酵
To pervade with a lightening, enlivening, or modifying influence.
充斥影響力：用輕松、活潑或變更的影響力來充斥

來源：
Middle English
中古英語
from Old French levain
源自 古法語 levain
from Vulgar Latin *lev3men
源自 俗拉丁語 *lev3men
from Latin lev3re [to raise] * see leg wh-
源自 拉丁語 lev3re [升起] *參見 leg wh-