U

chew the fat

verb (used with object)

to crush or grind with the teeth; masticate.
to crush, damage, injure, etc., as if by chewing (often followed by up): The faulty paper feeder chewed the letters up.
to make by or as if by chewing: The puppy chewed a hole in my slipper.
to meditate on; consider deliberately (often followed by over): He chewed the problem over in his mind.

verb (used without object)

to perform the act of crushing or grinding with the teeth.
Informal. to chew tobacco.
to meditate.

noun

an act or instance of chewing.
something chewed or intended for chewing: a chew of tobacco; taffy chews.

Verb Phrases

chew out, Slang. to scold harshly: The sergeant chewed out the recruits.

Idioms

chew the fat, Informal. to converse at length in a relaxed manner; chat: They liked to sit around chewing the fat.Also chew the rag.

verb

to work the jaws and teeth in order to grind (food); masticate
to bite repeatedlyshe chewed her nails anxiously
(intr) to use chewing tobacco
chew the fat or chew the rag slang
1. to argue over a point
2. to talk idly; gossip

noun

the act of chewing
something that is cheweda chew of tobacco

Old English ceowan “to bite, gnaw, chew,” from West Germanic *keuwwan (cf. Middle Low German keuwen, Dutch kauwen, Old High German kiuwan, German kauen), from PIE root *gyeu- “to chew” (cf. Old Church Slavonic živo “to chew,” Lithuanian žiaunos “jaws,” Persian javidan “to chew”).

Figurative sense of “to think over” is from late 14c.; to chew the rag “discusss some matter” is from 1885, apparently originally British army slang. Related: Chewed; chewing. To chew (someone) out (1948) probably is military slang from World War II. Chewing gum is by 1843, American English, originally hardened secretions of the spruce tree.

c.1200, “an act of chewing,” from chew (v.). Meaning “wad of tobacco chewed at one time” is from 1725; as a kind of chewy candy, by 1906.

Also, chew the rag. Chat in a friendly, leisurely way, as in Let’s get together for coffee and chew the fat, or John and Dave spend hours just chewing the rag. Before the 1880s in Britain, chew the fat meant “to grumble or complain,” and chew the rag also has been used in this way. Today both expressions are largely synonyms for a friendly talk or gossip session. Why this idiom uses fat and rag is not known, but some speculate that fat refers to juicy items of gossip and rag to ladies’ sewing circles and the cloth they worked on while chatting.

In addition to the idioms beginning with chew

chew out
chew the cud
chew the fat

also see:

bite off more than one can chew