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¹fat

adjective \ˈfat\

: having a lot of extra flesh on your body : having a lot of body fat

: having a full, rounded form

: unusually wide or thick

fat·terfat·test

Full Definition of FAT

: notable for having an unusual amount of fat:

a : plump

b : obese

c of a meat animal : fattened for market

d of food : oily, greasy

a : well filled out : thick, big <a fat book>

b : full in tone and quality : rich <a gorgeous fat bass voice — Irish Digest>

c : well stocked <a fat larder>

d : prosperous, wealthy <grew fat on the war — Time>

e : being substantial and impressive <a fat bank account>

a : richly rewarding or profitable <a fat part in a movie> <a fat contract>

b : practically nonexistent <a fat chance>

: productive, fertile <a fat year for crops>

: stupid, foolish

: being swollen <got a fat lip from the fight>

of a baseball pitch : easy to hit

— fat·ness noun

See fat defined for English-language learners

See fat defined for kids

Origin of FAT

Middle English, from Old English fǣtt, past participle of fǣtan to cram; akin to Old High German feizit fat

First Known Use: before 12th century

Related to FAT

Synonyms: blubbery, chubby, corpulent, fleshy, full, gross, lardy, obese, overweight, plump, podgy [chiefly British], portly, pudgy, replete, roly-poly, rotund, round, tubby

Antonyms: lean, skinny, slender, slim, spare, thin

Other Food Terms

Reuben, calamari, chuck, curry, edamame, foie gras, hummus, leaven, nonpareil, peel

Rhymes with FAT

bat, batt, blat, brat, cat, Cat, chat, chert, drat, flat, frat, gat, gnat, hat, mat, Matt, matte, pat, phat, plait, plat, Pratt, rat, sat, scat, scatt, skat, slat, spat, splat, sprat, stat, tat, that, vat

²fat

verb

fat·tedfat·ting

Definition of FAT

transitive verb

: to make fat : fatten

First Known Use of FAT

before 12th century

³fat

noun

: the soft flesh on the bodies of people and animals that helps keep the body warm and is used to store energy

: an oily solid or liquid substance in food

: an amount that is more than what is usual or needed

Full Definition of FAT

: animal tissue consisting chiefly of cells distended with greasy or oily matter

a : oily or greasy matter making up the bulk of adipose tissue and often abundant in seeds

b : any of various compounds of carbon, hydrogen, and oxygen that are glycerides of fatty acids, are the chief constituents of plant and animal fat, are a major class of energy-rich food, and are soluble in organic solvents but not in water

c : a solid or semisolid fat as distinguished from an oil

: the best or richest part

: obesity

: something in excess : superfluity <trim the fat from the news operation — Ray Olson>

— fat·less \-ləs\ adjective

See fat defined for English-language learners

First Known Use of FAT

14th century

Related to FAT

Synonyms: A-list, aristocracy, best, choice, corps d'elite, cream, crème de la crème, elect, elite, flower, illuminati, pick, pink, pride, priesthood, prime, royalty, upper crust

Antonyms: deficiency, deficit, insufficiency, undersupply

Other Biochemistry Terms

bile, biodegradable, capsaicin, keratin, metabolism

FATLESS Defined for Kids

¹fat

adjective \ˈfat\

fat·terfat·test

Definition of FAT for Kids

: having much body fat <a fat pig>

: ¹thick 1 <a fat book>

: richly rewarding or profitable <He signed a fat contract.>

: swollen up <I fell and got a fat lip.>

— fat·ness noun

²fat

noun

Definition of FAT for Kids

: animal or plant tissue containing much greasy or oily material

: any of numerous compounds of carbon, hydrogen, and oxygen that make up most of animal or plant fat and that are important to nutrition as sources of energy

: a solid fat as distinguished from an oil

: the best or richest part <the fat of the land>