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Synonyms

fat

American  
[fat] / fæt /

adjective

fatter, comparative fattest superlative
  1. having too much flabby tissue; corpulent; obese.

    a fat person.

    Synonyms:
    pudgy, adipose, portly
    Antonyms:
    thin
  2. plump; well-fed.

    a good, fat chicken.

  3. consisting of or containing fat; greasy; oily.

    fat gravy; fat meat.

    Synonyms:
    fatty, unctuous
    Antonyms:
    lean
  4. profitable, as an office.

    a fat job on the city commission.

    Synonyms:
    remunerative, lucrative
  5. affording good opportunities, especially for gain.

    a fat business contract.

  6. wealthy; prosperous; rich.

    He grew fat on dishonest profits.

  7. big, broad, or extended; thick.

    a fat sheaf of bills.

  8. plentiful; abundant.

    a fat supply of food.

    Synonyms:
    copious
  9. plentifully supplied.

    a fat larder; a fat feast.

  10. dull; stupid.

    fat clumsiness of manner.

    Synonyms:
    sluggish
    Antonyms:
    clever
  11. abounding in a particular element.

    Fat pine is rich in resin.

  12. (of paint) having more oil than pigment.

  13. (of coal) highly bituminous; rich in volatile hydrocarbons.

  14. Ceramics. long.

  15. fertile, as land.

    Everything grows in this fat soil.

    Synonyms:
    productive, fruitful, rich
    Antonyms:
    barren, sterile

noun

fats plural
  1. any of several white or yellowish greasy substances, forming the chief part of adipose tissue of animals and also occurring in plants, that when pure are colorless, odorless, and tasteless and are either solid or liquid esters of glycerol with fatty acids; fats are insoluble in water or cold alcohol but soluble in ether, chloroform, or benzene: used in the manufacture of soap, paints, and other protective coatings and in cooking.

  2. animal tissue containing much of this substance; loose flesh; flabbiness.

    to have rolls of fat around one's waist.

  3. the richest or best part of anything.

  4. obesity; corpulence.

    In his later years, he inclined to fat.

  5. Slang. especially profitable or advantageous work.

  6. an overabundance or excess; superfluity.

  7. action or lines in a dramatic part that permit an actor to display abilities.

  8. Also called liftTypesetting. Also matter that can be composed easily and profitably, especially from standing type, illustrations, or the like.

    fat work.

verb (used with or without object)

fats, present (3rd person singular) fatted, past participle, past fatting present participle
  1. to make or become fat.

idioms

  1. chew the fat. chew.

  2. the fat of the land, the best or richest of anything obtainable.

    to live on the fat of the land.

  3. a fat chance, a very slight chance; small probability.

    A fat chance he has of winning the title!

  4. the fat is in the fire,

    1. an irrevocable action or chain of events has been started; the die is cast.

      Now that they have been given an ultimatum, the fat is in the fire.

    2. the decision, whether good or bad, has been made.

    3. the crisis is imminent.

  5. a fat lot, little or not at all.

    A fat lot they care about anyone else's troubles!

fat British  
/ fæt /

noun

  1. any of a class of naturally occurring soft greasy solids that are esters of glycerol and certain fatty acids. They are present in some plants and in the adipose tissue of animals, forming a reserve energy source, and are used in making soap and paint and in the food industry See also oil

  2. vegetable or animal tissue containing fat

  3. corpulence, obesity, or plumpness

  4. the best or richest part of something

  5. a part in a play that gives an actor a good opportunity to show his talents

  6. slang

    1. to argue over a point

    2. to talk idly; gossip

  7. an irrevocable action has been taken, esp one from which dire consequences are expected

  8. the best that is obtainable

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

adjective

  1. having much or too much flesh or fat

  2. consisting of or containing fat; greasy

    fat pork

  3. profitable; lucrative

    a fat year

  4. affording great opportunities

    a fat part in the play

  5. fertile or productive

    a fat land

  6. thick, broad, or extended

    a fat log of wood

  7. having a high content of a particular material or ingredient, such as resin in wood or oil in paint

  8. plentifully supplied

    a fat larder

  9. slang empty; stupid

    get this into your fat head

  10. slang very little or none; minimal (in phrases such as a fat chance , a fat lot of good , etc)

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

verb

  1. to make or become fat; fatten

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
fat Scientific  
/ făt /
  1. Any of a large number of oily compounds that are widely found in plant and animal tissues and serve mainly as a reserve source of energy. In mammals, fat, or adipose tissue, is deposited beneath the skin and around the internal organs, where it also protects and insulates against heat loss. Fat is a necessary, efficient source of energy. An ounce of fat contains more than twice as much stored energy as does an ounce of protein or carbohydrates and is digested more slowly, resulting in the sensation of satiety after eating. It also enhances the taste, aroma, and texture of food. Fats are made chiefly of triglycerides, each molecule of which contains three fatty acids. Dietary fat supplies humans with essential fatty acids, such as linoleic acid and linolenic acid. Fat also regulates cholesterol metabolism and is a precursor of prostaglandins.

  2. See more at saturated fat unsaturated fat


fat More Idioms  

    More idioms and phrases containing fat


Usage

What is a basic definition of fat? Fat is commonly used as a way to describe someone as obese or overweight. This is most often used in a critical, judgmental, or mean way. In contrast, words like obese and overweight are more often used in a neutral way, such as in a medical context in the discussion of a person’s health (though they too can be used in a judgmental or mean way). This sense of fat isn’t always used in a negative way. Some people might call others or themselves fat in a way that’s not intended to be critical, as in I’m fat and I’m fabulous and all the body-shamers will just have to deal with it. Sometimes, people replace the word fat with words intended to be more polite or euphemistic, such as heavy, heavyset, plump, and chubby. However, these words still focus on a person’s weight or appearance in a way that can be demeaning or objectifying. As a noun, fat refers to the greasy substance that forms some types of tissue in the body of humans and animals (some of which the body stores and uses for energy) and some plants. The word is often used more casually to refer to a person’s excess flesh, as in belly fat.  In the context of nutrition, fat refers to this kind of substance in the foods we eat. Foods from animals, such as meat, milk, and eggs, all contain fat. But so do some plant-based foods, such as nuts, avocados, and olive oil. However, there are different kinds of fat, such as saturated fat, unsaturated fat, and trans-fat, each of which can have different effects on a person’s nutrition and health. In general, it’s usually recommended not to consume too much fat. However, some fats are necessary in a diet because they help the body to absorb vitamins. The nutrition label on food products usually tell you exactly how much fat and what kinds of fats are in them. The word fat is common and has many other meanings as an adjective, a noun, and even a verb. Example: This diet is based on avoiding foods that are high in fat.  

Synonym Usage

See stout.

Other Word Forms

Derived Forms

Inflected Forms

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Adjectives

Participles

Conjugated Forms

Present

Past

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Etymology

Origin of fat

First recorded before 1000; Middle English; Old English fǣtt, originally the past participle of fǣtan “to cram, load, adorn”; cognate with Gothic fētjan “to adorn”; akin to vat

Explanation

Fat is a form of body tissue on animals. It’s a squishy layer that stores energy and protects organs. Fat is also an adjective meaning chubby or thick, as in a fat piglet or a fat wallet full of money. Some foods, like butter or avocado, have fat. Deep fried chocolate bars have a lot of fat. Humans, and other animals, need to consume some fat to maintain optimal health and absorb certain vitamins. The word fat can be applied not just to people, animals, or deep-fried food, but to any inanimate object that is notably big. Your brother likes reading comics, while you prefer fat books like War and Peace and The Complete Works of Shakespeare.

Keep Reading on Vocabulary.com

Vocabulary lists containing fat

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

See Examples For:

Lower levels of these harmful fat deposits may reduce inflammatory signals that contribute to aging throughout the body.

From Science Daily Jul. 14, 2026

Spatchcock it, score the fat so it can render as it smokes and place a pan beneath the bird to catch the liquid gold that is duck fat.

From Salon Jul. 12, 2026

Some list what they’re eating and ask how they could eat better, sometimes getting dangerous responses about cutting out too much fat and carbs.

From The Wall Street Journal Jul. 11, 2026

The same research found, external that women also have a higher core body temperature and body fat percentage than men, which acts like an extra insulating layer.

From BBC Jul. 8, 2026

The engine gave out a sudden gunned roar as he rolled the fat car up really fast, then braked sharply, three or four feet away from me.

From "Firegirl" by Tony Abbott

"We discovered that deleting Mitch led to a major drop in fats in membranes," Gross explains.

From Science Daily Jul. 3, 2026

The other helps mitochondria process certain fats and protein building blocks.

From Science Daily Jun. 25, 2026

You can also add granola with oats and nuts that contribute healthy fats that slow glucose absorption.

From MarketWatch Jun. 21, 2026

They contain nitrates, high levels of sodium and saturated fats, and aromatic hydrocarbons that increase the risk of cancer, hypertension, and heart disease.

From MarketWatch Jun. 21, 2026

So if you wonder why Americans are so obese, consider the fact that waitresses both express their humanity and earn their tips through the covert distribution of fats.

From "Nickel and Dimed: On (Not) Getting By in America" by Barbara Ehrenreich

Boosting isn’t a solution, but it is an equalizer, reminding upper management that a different title and fatter salary don’t exempt them from compassion, inside or outside the store.

From Salon May 22, 2026

SNPs have even fatter profit margins than traditional Medicare Advantage plans.

From MarketWatch Mar. 6, 2026

Price/earnings multiples are largely higher for companies with fatter gross margins, Trivariate’s data show, so disappointments on margins would reduce multiples—and cause individual stocks to fall.

From Barron's Feb. 27, 2026

Her agenda includes new investment in strategic industries, temporary tax relief for inflation-weary consumers and fatter defense budgets.

From The Wall Street Journal Feb. 9, 2026

I almost want to stay and hear where this goes, but my fat lip is getting fatter.

From "The Sun Is Also a Star" by Nicola Yoon

This is partly why she pursued the research: She wanted to figure out what characterizes the few with the fattest paychecks.

From The Wall Street Journal Apr. 30, 2026

“America has now become the fattest nation in the world. Congratulations,” a voice narrates.

From New York Times May 12, 2024

And second, Sgr A* isn't even the fattest hole we've seen.

From Salon Mar. 28, 2024

“I’m telling you it is the fattest snake I’ve ever seen in my life. It was insane,” Ms. Siewe told the Sun Sentinel.

From Washington Times Nov. 9, 2023

One was plainly meant to be Lord Manderly; it was the fattest snowman that Theon had ever seen.

From "A Dance with Dragons" by George R. R. Martin

Finally, with the infrastructure in place and the new money flowing, the Dodgers then opened their fatted wallet for the players that created the championship.

From Los Angeles Times Dec. 4, 2024

You were the good and prudent child, and now you’re glumly getting ready for the fatted calf to be slaughtered for your useless brother.

From Slate Feb. 22, 2019

“The Ranch” is a prodigal-son story, complete with fatted calves.

From New York Times Mar. 31, 2016

Feasting on the fatted calf of divine grace, every day was thanksgiving.

From Time Feb. 13, 2015

‘And we’ll kill the fatted calf—you long-lost whatever-you-are. Come an hour after candles are lit. Prodigal Son, what? Got a cup, has he?’

From "Johnny Tremain" by Esther Hoskins Forbes

"I had three weeks off after the US Open and you probably saw a little bit on Thursday I was fatting a few shots," said Hatton.

From BBC Jul. 14, 2023

Even when steep swingers hit it solid, they take deep divots—they're always on the verge of fatting it.

From Golf Digest Mar. 13, 2017

All, except the fatting sheep, were folded on the stubbles, and allowed a daily run on the park of about an hour for each flock.

From The Stock-Feeder's Manual the chemistry of food in relation to the breeding and feeding of live stock by Cameron, Charles Alexander, Sir

Nothing is paid for a dry cow, and therefore tithe in kind must be paid for all fatting cattle.

From A Cotswold Village by Gibbs, J. Arthur

The sow must live as well as a fatting hog, or the pigs will be good for little.

From Cottage Economy To Which Is Added The Poor Man's Friend by Cobbett, William

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