fat

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun The ester of glycerol and one, two, or three fatty acids.
• noun Any of various soft, solid, or semisolid organic compounds constituting the esters of glycerol and fatty acids and their associated organic groups.
• noun A mixture of such compounds occurring widely in organic tissue, especially in the adipose tissue of animals and in the seeds, nuts, and fruits of plants.
• noun Animal tissue containing such substances.
• noun A solidified animal or vegetable oil.
• noun Obesity; corpulence.
• noun Unnecessary excess.
• adjective Having much or too much fat or flesh; plump or obese.
• adjective Full of fat or oil; greasy.
• adjective Abounding in desirable elements.
• adjective Fertile or productive; rich.
• adjective Having an abundance or amplitude; well-stocked.
• adjective Yielding profit or plenty; lucrative or rewarding.
• adjective Prosperous; wealthy.
• adjective Thick; large.
• adjective Puffed up; swollen.
• transitive & intransitive verb To make or become fat; fatten.
• idiom (a fat lot) Very little or none at all.
• idiom (fat chance) Very little or no chance.
• idiom (the fat is in the fire) Bad consequences are sure to follow; trouble lies ahead.

from The Century Dictionary.

• noun A large open vessel for water, wine, or other liquids; a tub; a cistern: now usually vat (which see).
• noun A dry measure, generally equal to 9 bushels.
• Having much flesh other than muscle; having an unusual amount of flesh; corpulent; obese: as, a fat man; a fat ox.
• Containing the substance called fat (see II.); containing or consisting of fat, oil, or grease; oily; greasy; unctuous: as, a fat dish; fat cheese.
• Hence Containing much resin; resinous: as, fat pine.
• Containing much plastic or unctuous matter; pinguid: said of clay which is free from intermingled sand, and consequently highly plastic; or of lime made from limestone which contains but a small amount (ten per cent. or less) of the ordinary impurities of limestone — silica, alumina, oxid of iron, etc.
• Having or showing, in mind or movement, the qualities of a fat animal; heavy; dull; stupid.
• Well supplied with what is needful or desired; abounding in comforts; prosperous.
• Abundant in production, or yielding large profits; rich in results or yield; profitable.
• Nautical, broad, as the quarter of a ship.
• noun A white or yellowish oily solid substance forming the chief part of the adipose tissue of animals, and also found in plants.
• noun The best or richest part of a thing.
• noun In type-setting, work which for any reason is unusually profitable to the compositor. See fat work, above.
• To make fat; fatten.
• To become fat; grow fat.
• In leather-manuf, to smear over with a heavy oil.
• In painting, rich; full of color.
• noun A local Australian term for fat or marketable cattle.

from the GNU version of the Collaborative International Dictionary of English.

• noun obsolete A large tub, cistern, or vessel; a vat.
• noun obsolete A measure of quantity, differing for different commodities.
• adjective Abounding with fat.
• adjective Fleshy; characterized by fatness; plump; corpulent; not lean.
• adjective Oily; greasy; unctuous; rich; -- said of food.
• adjective Exhibiting the qualities of a fat animal; coarse; heavy; gross; dull; stupid.
• adjective Fertile; productive
• adjective Rich; producing a large income; desirable
• adjective obsolete Abounding in riches; affluent; fortunate.