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

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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 lift. Typesetting. 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

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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)

verb

1. to make or become fat; fatten

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

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fat More Idioms  

More idioms and phrases containing fat

• chew the fat
• kill the fatted calf

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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

• fatness
  noun
• defat
  verb (used with object)
• fatless
  adjective
• fatlike
  adjective
• fattish
  adjective
• overfat
  adjective
• unfatted
  adjective
• fatly
  adverb

Inflected Forms

Nouns

• fats
  plural

Adjectives

• fatter
  comparative
• fattest
  superlative

Participles

• fatting
  present
• fatted
  past

Conjugated Forms

Present

• fat
  simple
• fats
  simple
• have fatted
  perfect
• has fatted
  perfect
• am fatting
  progressive
• are fatting
  progressive
• is fatting
  progressive
• have been fatting
  perfect progressive
• has been fatting
  perfect progressive

Past

• fatted
  simple
• had fatted
  perfect
• was fatting
  progressive
• were fatting
  progressive
• had been fatting
  perfect progressive

Future

• will fat
  simple
• will have fatted
  perfect
• will be fatting
  progressive
• will have been fatting
  perfect progressive

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.

Example Sentences

See Examples For:

fat fats fatter fattest fatted fatting

While we tend to think that carbs promote fat storage, Whitson said that when leveraged correctly, this isn’t true.

From Slate ● Oct. 9, 2026

On social media, influencers and fitness experts garner millions of views and likes on videos blaming cortisol for an array of concerns from belly fat to hair loss to “moon face.”

From Slate ● Oct. 9, 2026

When exercise stimulates PLIN1, it changes and releases ABHD5, which helps initiate fat breakdown.

From Science Daily ● Oct. 8, 2026

Gym rats can check their body composition of fat and muscle, people with heart issues can get their heartbeat captured, and mole owners can get their moles mapped to 0.1 mm.

From Slate ● Oct. 8, 2026

But family is family, and I’ll stick with her like a tick on a fat dog.

From "The Detective's Assistant" by Kate Hannigan

The results showed no meaningful differences in blood lipid levels between those consuming dairy foods with higher levels of natural trans fats and those consuming regular dairy products.

From Science Daily ● Oct. 8, 2026

They occur naturally in the milk of animals such as cows, sheep, and goats, but they can also be produced artificially during the manufacture of partially hydrogenated fats.

From Science Daily ● Oct. 8, 2026

Across these studies, higher levels of dairy trans fats were not associated with an increased risk of heart disease, stroke or cardiovascular death.

From Science Daily ● Oct. 8, 2026

Their findings indicate that naturally occurring dairy trans fats act differently in the body from industrial trans fats.

From Science Daily ● Oct. 8, 2026

Trans fats are also used in processed snacks, baked goods, and many other processed foods.

From "The Omnivore's Dilemma" by Michael Pollan

Campbell says they "played around" with how much the ball was blown up, adding: "In previous weeks it was actually a bit fatter, and then this week it definitely feels smaller."

From BBC ● Sep. 7, 2026

I never became “unrecognizable,” and I spent more time than I’d like to admit looking at myself in the mirror and comparing what I saw to photos of the younger, fatter version of myself.

From Los Angeles Times ● Aug. 12, 2026

But weakening domestic sales are pushing manufacturers like Zhang to seek fatter margins abroad, where consumers have more purchasing power.

From Barron's ● Aug. 9, 2026

Investors zero in on United’s potentially fatter jet-fuel bill — the airline said it expects nearly $6 billion in additional fuel expenses for the year.

From The Wall Street Journal ● Jul. 17, 2026

My sister asked nervous questions about what college is “really” like and would she put on the “freshman fifteen”? I don’t know what this is, but I’m guessing it means you get fatter.

From "The Perks of Being a Wallflower" by Stephen Chbosky

Sometimes we all need some joy in life, such as contemplating the fattest bears without all the other gloomy stuff in the world.

From Salon ● Sep. 26, 2026

“It’s the early Christian that gets the fattest lion.”

From MarketWatch ● Jul. 24, 2026

“The fattest chicken is in Belgium but there are other chickens around,” De Wever said last month.

From The Wall Street Journal ● Nov. 15, 2025

The fattest part of the barrel is actually closer to the handle, with the idea of redistributing more mass to an area where some hitters make more frequent contact.

From Los Angeles Times ● Apr. 4, 2025

And worst of all, Cara thought, “I would know that I am the biggest, fattest, weakest, lamest, chickenest coward who ever lived.”

From "The Landry News" by Andrew Clements

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

“If you have a fatted goose, it’s not going to walk well,” he says.

From Slate ● Sep. 20, 2015

After expending hundreds of angry words, he noted that he is one of 32 terrifically rich owners and everyone loves a fatted calf.

From New York Times ● May 6, 2015

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

It originally meant food used for fatting, especially for fatting swine.

From The plant-lore & garden-craft of Shakespeare by Henry Nicholson Ellacombe

It is then ready for use, to be carried to the pigs in the stalls alongside the fatting beasts.

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

The nutritious nature of barley is amply proved by the effect, and very rapid effect, of its meal, in the fatting of hogs and of poultry of all descriptions.

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

Related Words

• big
• bulging
• bulky
• chunky
• heavy
• hefty
• inflated
• large
• meaty
• obese
• plump
• well-fed