fat

Concise Oxford English Dictionary © 2008 Oxford University Press:
fat/fat/

▶noun

• 1 a natural oily substance in animal bodies, especially when deposited under the skin or around certain organs.

  ■ such a substance, or a similar one made from plants, used in cooking.

• 2 the presence of excess fat in a person or animal: he was running to fat.

• 3 Chemistry any of a group of natural esters of glycerol and various fatty acids, which are solid at room temperature and are the main constituents of animal and vegetable fat. Compare with oil.

▶adjective (fatter, fattest)

• 1 (of a person or animal) having a lot of excess fat.

• 2 (of food) containing much fat.

• 3 informal substantial: fat profits.

• 4 informal used to express the belief that something is unlikely: fat chance she had of influencing him.

▶verb (fats, fatting, fatted) archaic make or become fat.

– phrases
the fat is in the fire something has happened that will inevitably cause trouble.
kill the fatted calf produce one's best food to celebrate, especially at a prodigal's return. [with biblical allusion to Luke 15.]
live off (or on) the fat of the land have the best of everything.

– derivatives
fatless adjective,
fatly adverb,
fatness noun,
fattish adjective.

– origin OE fǣtt, of W. Gmc origin.