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.

Definitions of fat
  1. noun
    a soft greasy substance occurring in organic tissue and consisting of a mixture of lipids (mostly triglycerides)
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    edible fat
    oily or greasy matter making up the bulk of fatty tissue in animals and in seeds and other plant tissue
    animal fat
    any fat obtained from animals
    cocoa butter
    a yellow-white fat from cocoa beans
    leaf fat, leaf lard
    fat lining the abdomen and kidneys in hogs which is used to make lard
    medulla, myelin, myeline
    a white fatty substance that forms a medullary sheath around the axis cylinder of some nerve fibers
    polyunsaturated fat
    a class of fats having long carbon chains with many double bonds unsaturated with hydrogen atoms; used in some margarines; supposedly associated with low blood cholesterol
    the crisp residue left after lard has been rendered
    soft white semisolid fat obtained by rendering the fatty tissue of the hog
    the intermixture of fat and lean in a cut of meat
    fat such as butter or lard used in baked goods
    hard fat around the kidneys and loins in beef and sheep
    fat that exudes from meat and drips off while it is being roasted or fried
    oil, vegetable oil
    any of a group of liquid edible fats that are obtained from plants
    bone fat
    fatty matter in bones extracted with solvents or by boiling or steaming; used chiefly in candles and cheap soaps and in lubricating greases
    the fatty substance of milk from which butter is made
    type of:
    lipid, lipide, lipoid
    an oily organic compound insoluble in water but soluble in organic solvents; essential structural component of living cells (along with proteins and carbohydrates)
  2. noun
    a kind of body tissue containing stored fat that serves as a source of energy; it also cushions and insulates vital organs
    synonyms: adipose tissue, fatty tissue
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    loose or flaccid body fat
    a fatty deposit in the intima (inner lining) of an artery; can obstruct blood flow
    lumpy deposits of body fat especially on women's thighs etc.
    puppy fat
    fat on the body of a baby or child; disappears at adolescence
    mons, mons pubis, mons veneris
    a mound of fatty tissue covering the pubic area in women
    belly, paunch
    a protruding abdomen
    love handle, spare tire
    excess fat around the waistline
    bay window, corporation, pot, potbelly, tummy
    slang for a paunch
    type of:
    animal tissue
    the tissue in the bodies of animals
  3. noun
    excess bodily weight
    synonyms: avoirdupois, blubber, fatness
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    leanness, spareness, thinness
    the property of having little body fat
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    adiposeness, adiposity, fattiness
    having the property of containing fat
    abdominousness, paunchiness
    the bodily property of a protruding belly
    greasiness, oiliness, oleaginousness
    consisting of or covered with oil
    corpulency, fleshiness, obesity
    more than average fatness
    an extreme accumulation of fat on the buttocks
    adiposis, corpulence, overweight, stoutness
    the property of excessive fatness
    exogenous obesity
    obesity caused by overeating
    embonpoint, plumpness, roundness
    the bodily property of being well rounded
    type of:
    bodily property
    an attribute of the body
  4. adjective
    containing or composed of fat
    fat tissue”
    synonyms: fatty
    composed of animal fat
    resembling or containing or spread with butter
    greasy, oily, oleaginous, sebaceous, unctuous
    containing an unusual amount of grease or oil
    like or full of suet
    (of soap) containing extra unsaponified fat
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    fat-free, fatless, nonfat
    without fat or fat solids
    calorie-free, light, lite, low-cal
    having relatively few calories
    skim, skimmed
    used of milk and milk products from which the cream has been removed
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  5. adjective
    having an (over)abundance of flesh
    endomorphic, pyknic
    having a squat and fleshy build
    abdominous, paunchy, potbellied
    having a large belly
    swollen with fat
    chubby, embonpoint, plump
    sufficiently fat so as to have a pleasing fullness of figure
    buxom, zaftig, zoftig
    (of a female body) healthily plump and vigorous
    corpulent, obese, rotund, weighty
    excessively fat
    double-chinned, jowly, loose-jowled
    having sagging folds of flesh beneath the chin or lower jaw
    dumpy, podgy, pudgy, roly-poly, tubby
    short and plump
    somewhat fat
    fleshy, heavy, overweight
    usually describes a large person who is fat but has a large frame to carry it
    gross, porcine
    repellently fat
    portly, stout
    euphemisms for `fat'
    curving and somewhat round in shape rather than jagged
    not thin; of a specific thickness or of relatively great extent from one surface to the opposite usually in the smallest of the three solid dimensions
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    lean, thin
    lacking excess flesh
    having a build with little fat or muscle but with long limbs
    anorectic, anorexic
    suffering from anorexia nervosa; pathologically thin
    bony, cadaverous, emaciated, gaunt, haggard, pinched, skeletal, wasted
    very thin especially from disease or hunger or cold
    deep-eyed, hollow-eyed, sunken-eyed
    characteristic of the bony face of a cadaver
    gangling, gangly, lanky
    tall and thin
    lank, spindly
    long and lean
    having a lean and bony physique
    reedlike, reedy
    resembling a reed in being upright and slender
    twiggy, twiglike
    thin as a twig
    resembling a scarecrow in being thin and ragged
    boney, scraggy, scrawny, skinny, underweight, weedy
    being very thin
    shriveled, shrivelled, shrunken, withered, wizen, wizened
    lean and wrinkled by shrinkage as from age or illness
    slender, slight, slim, svelte
    being of delicate or slender build
    slender-waisted, slim-waisted, wasp-waisted
    having a small waist
    spare, trim
    thin and fit
    spindle-legged, spindle-shanked
    having long slender legs
    stringy, wiry
    lean and sinewy
    wisplike, wispy
    thin and weak
    of relatively small extent from one surface to the opposite or in cross section
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  6. verb
    make fat or plump
    synonyms: fatten, fatten out, fatten up, fill out, flesh out, plump, plump out
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    type of:
    alter, change, modify
    cause to change; make different; cause a transformation
  7. adjective
    having a relatively large diameter
    “a fat rope”
    not thin; of a specific thickness or of relatively great extent from one surface to the opposite usually in the smallest of the three solid dimensions
  8. adjective
    marked by great fruitfulness
    “a fat land”
    synonyms: fertile, productive, rich
    productive or conducive to producing in abundance
  9. adjective
    “a nice fat job”
    synonyms: juicy
    yielding material gain or profit
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