Dime
late Middle English: from Old French disme, from Latin decima pars ‘tenth part’. The word originally denoted a tithe or tenth part; the modern sense ‘ten-cent coin’ dates from the late 18th century.
wiktionary
Middle English dime, from Anglo-Norman disme(“one tenth, tithe”) (modern French dîme), from Latin decimus(“tenth”). [1] Doublet of decime.
From the use of the coin in a payphone to report a crime to the police. US payphones charged 10¢ in almost all jurisdictions until the late 1970s.
etymonline
dime (n.)
chosen 1786 as name for U.S. 10-cent coin (originally of silver), from dime "a tenth, tithe" (late 14c.), from Old French disme (Modern French dîme) "a tenth part" and directly from Medieval Latin decima, from Latin decima (pars) "tenth (part)," from decem "ten" (from PIE root *dekm- "ten").
The verb meaning "to inform" (on someone) is from the 1960s, from the then-cost of a pay-phone call. Alliterative phrase a dime a dozen "almost worthless" is recorded by 1930 (as an actual price, for eggs, etc., by 1861). Phrase stop on a dime attested by 1927 (a dime being the physically smallest unit of U.S. currency); turn on a dime is by 1913. Dime store "retail outlet selling everything for (more or less) 10 cents" is by 1928.
