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

Inflected Forms

Participles

• leavening
  present
• leavened
  past

Conjugated Forms

Present

• leaven
  simple
• leavens
  simple
• have leavened
  perfect
• has leavened
  perfect
• am leavening
  progressive
• are leavening
  progressive
• is leavening
  progressive
• have been leavening
  perfect progressive
• has been leavening
  perfect progressive

Past

• leavened
  simple
• had leavened
  perfect
• was leavening
  progressive
• were leavening
  progressive
• had been leavening
  perfect progressive

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

See Examples For:

leaven leavens leavened leavening

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

That’s in keeping with a director who likes to leaven something profound with something ordinary.

From Seattle Times ● May 28, 2024

There was gloss and sass to leaven the tough stuff.

From Los Angeles Times ● Mar. 27, 2024

I also used to leaven the proceedings with humor.

From Salon ● Feb. 2, 2024

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

A doleful tale, but Mr. Ogilvy also leavens it with humor.

From The Wall Street Journal ● Aug. 7, 2026

Whether the songs are presented in their orchestral splendor or as frenetic electronica, each needle drop leavens the natural comedy of John’s frantic awkwardness or captures his chronic sorrow.

From Salon ● Mar. 26, 2025

The yeast is tolerant of this acidic environment, and it ferments carbohydrates other than maltose to produce the carbon dioxide that leavens the bread.

From Scientific American ● Nov. 1, 2023

Nabeta has a no-nonsense directness that she leavens with a warm smile.

From Los Angeles Times ● May 6, 2022

Do you not know that a little leaven leavens the whole mass?

From The New Testament Translated From the Original Greek, With Chronological Arrangement of the Sacred Books, and Improved Divisions of Chapters and Verses. by Leicester A. (Leicester Ambrose) Sawyer

The 65-year-old came to court in downtown Los Angeles for closing arguments this month in one of the biggest trials of his career, armed with a parable of leavened bread.

From The Wall Street Journal ● Mar. 28, 2026

Closely cropped and dramatically lighted, the tight composition gives the familiar scene a new immediacy and intimacy, leavened by the playful interaction of the Christ child and St. John.

From The Wall Street Journal ● Mar. 24, 2026

What you might recognize as a modern-style fruitcake – a moist, leavened dessert studded with fruits and nuts – was probably first baked in the early Middle Ages in Europe.

From Salon ● Dec. 17, 2024

Arturo Enciso is known for the naturally leavened sourdough breads and pastries at his Long Beach bakery Gusto, including his hueso baguettes and conchas de cacao.

From Los Angeles Times ● Nov. 3, 2024

The guilt she feels at Gogol’s deflated expression is leavened by common sense.

From "The Namesake" by Jhumpa Lahiri

The natural leavening gives them a lighter, crispier crust and an airy, mildly tangy crumb.

From The Wall Street Journal ● May 9, 2026

They are also what make it rise in the absence of other leavening agents.

From Salon ● Apr. 30, 2024

A corrosive rage courses through this 163-minute odyssey that’s matched by a leavening absurdism, Jude aghast at the comical stupidity of our inauthentic, greed-driven world.

From Los Angeles Times ● Mar. 20, 2024

But I do depart from my standard in one major way: Swirled brownies need leavening.

From Washington Post ● Dec. 7, 2022

From morning to night, he displayed cool and reasoned leadership, with his humor leavening even the most difficult crisis.

From "Long Walk to Freedom" by Nelson Mandela

Related Words

• imbue
• infuse