c. 1300, "a wedge, a wedge-shaped piece used for some purpose," from Old French coing (12c.) "a wedge; stamp; piece of money;" usually "corner, angle," from Latin cuneus "a wedge," which is of unknown origin.

The die for stamping metal was wedge-shaped, and by late 14c. the English word came to mean "thing stamped, piece of metal converted into money by being impressed with official marks or characters" (a sense that already had developed in Old French). Meaning "coined money collectively, specie" is from late 14c.

Compare quoin, which split off from this word 16c., taking the architectural sense. Modern French coin is "corner, angle, nook."

The custom of striking coins as money began in western Asia Minor in 7c. B.C.E.; Greek tradition and Herodotus credit the Lydians with being first to make and use coins of silver and gold. Coin-operated (adj.), of machinery, is attested from 1890. Coin collector is attested from 1795.

mid-14c., "to make (coins) by stamping metals;" early 15c., "to stamp (metal) and convert it into coins," from coin (n.). General sense of "make, fabricate, invent" (words) is from 1580s; the phrase coin a phrase is attested from 1940 (to coin phrasesis from 1898). A Middle English word for minter was coin-smiter. Related: Coined; coining.

1530s, in architecture and masonry, "cornerstone, external solid angle," a variant spelling of coin (n.); in early use also in other senses of that word, including "a wedge, wedge-like piece of stone, wood, etc."

late 14c., "currency, coined money," from Old French coignage, from coignier "to coin," from coing "piece of money: (see coin (n.)). Meaning "act or process of coining money" is from early 15c.; sense "deliberate formation of a new word" is from 1690s, from a general sense of "something invented" (c. 1600).

1804, "coin of small value," in early use the Spanish half-real, a coin circulating in Louisiana, Florida, and adjacent regions, worth about 6 cents, later a 5 cent piece; probably from Louisiana French picaillon "coin worth 5 cents," earlier the French name of an old copper coin of Savoy (1750), from Provençal picaioun "small copper coin," from picaio "money," a word of uncertain origin. Adjectival figurative sense of "paltry, mean" recorded from 1813.

medieval French silver coin corresponding to the English penny, early 15c., from Old French dener, a small coin of slight value, roughly equivalent to the English penny, in use in France from the time of Charlemagne to early modern times, from Latin denarium, from denarius, name of a Roman coin (source also of Spanish dinero); see denarius.