"Leaven" is a word in ENGLISH

leaven ENGLISH
Definition:

Any substance that produces, or is designed to produce,
fermentation, as in dough or liquids; esp., a portion of fermenting
dough, which, mixed with a larger quantity of dough, produces a general
change in the mass, and renders it light; yeast; barm.

leaven ENGLISH
Definition:

To imbue; to infect; to vitiate.

leaven ENGLISH
Definition:

To make light by the action of leaven; to cause to
ferment.

leaven ENGLISH
Definition:

Anything which makes a general assimilating (especially a
corrupting) change in the mass.

Few words of positivity

How can a man’s candour be seen in all its lustre unless he has a few failings to talk of? But he had an agreeable confidence that his faults were all of a generous kind—impetuous, arm-blooded, leonine; never crawling, crafty, reptilian.

George Eliot, Adam Bede

WORD SUGGESTIONS
Laugh your heart out.

Why was the cowboy a lot of laughs?He was always horsing around.

yeast ENGLISH

The foam, or troth (top yeast), or the sediment (bottom yeast), of beer or other in fermentation, which contains the …

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