leaven

American  

[lev-uhn] / ˈlɛv ən /

noun

1. a substance, as yeast or baking powder, that causes fermentation and expansion of dough or batter.

2. fermented dough reserved for producing fermentation in a new batch of dough.

3. an element that produces an altering or transforming influence.

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verb (used with object)

leavens, present (3rd person singular) leavened, past participle, past leavening present participle

1. to add leaven to (dough or batter) and cause to rise.

2. to permeate with an altering or transforming element.

leaven British  

/ ˈlɛvən /

noun

1. any substance that produces fermentation in dough or batter, such as yeast, and causes it to rise

2. a piece of such a substance kept to ferment a new batch of dough

3. an agency or influence that produces a gradual change

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verb

1. to cause fermentation in (dough or batter)

2. to pervade, causing a gradual change, esp with some moderating or enlivening influence

Other Word Forms

Conjugated Forms

Present

• has leavened
  perfect 3rd person singular
• have leavened
  perfect
• are leavening
  progressive
• is leavening
  progressive 3rd person singular
• am leavening
  progressive 1st person singular
• have been leavening
  perfect progressive
• has been leavening
  perfect progressive 3rd person singular
• leavens
  singular 3rd person
• leavening
  participle

Past

• had leavened
  perfect
• was leavening
  progressive singular
• were leavening
  progressive plural
• had been leavening
  perfect progressive
• leavened
  simple
• leavened
  participle

Future

• will leaven
  simple
• will have leavened
  perfect
• will be leavening
  progressive
• will have been leavening
  perfect progressive

Etymology

Origin of leaven

First recorded in 1300–50; Middle English levain, levein, leven, from Anglo-French levein, levain, Old French levain, from Vulgar Latin levāmen (unrecorded) “means of raising or lifting,” from Latin levāmen “alleviation, mitigation, relief,” derivative of levā(re) “to raise, lift up; relieve, reduce” + -men noun suffix

Explanation

Leaven, as a noun, is that which causes transformation. It’s the source of yeast that makes your bread rise, it’s the risen bread, and it’s anything that changes the nature of something else. Coming through Old French from the Latin verb levare, which means “to raise,” leaven changes everything. It makes dough go from flat to loaf, and it’s also the term to describe the risen dough before it’s baked. And leaven can be anything that causes transformation — "Winning the lottery will be the leaven that allows you to travel the world." Additionally it’s a verb: "When you bake bread, you leaven the dough to make it rise."

Example Sentences

If Ms. Gage wanted some celebratory leaven, she could have visited Dayton, Ohio’s many sites devoted to the Wright Brothers and their world-changing invention.

From The Wall Street Journal • Apr. 1, 2026

Port cities teem with elegant sailing ships, costumes are colorful and pockets of humor and romance leaven the action sequences.

From Seattle Times • Feb. 21, 2024

She tries to leaven that determination by arguing that Congress would be unlikely to pass one.

From Los Angeles Times • Jan. 26, 2024

In the evening we will start with the first dough and when it's complete we let it leaven and rise overnight.

From Salon • Apr. 8, 2023

For one thing, any hopes my father may have had that to meet the General in person would arouse a sense of respect or sympathy to leaven his feelings against him proved without foundation.

From "The Remains of the Day" by Kazuo Ishiguro

Related Words

• imbue
• infuse