Etymology
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adapt (v.)
Origin and meaning of adapt

early 15c. (implied in adapted) "to fit (something, for some purpose)," from Old French adapter (14c.), from Latin adaptare "adjust, fit to," from ad "to" (see ad-) + aptare "to join," from aptus "fitted" (see apt). Intransitive meaning "to undergo modification so as to fit new circumstances" is from 1956. Related: Adapting.

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adaptive (adj.)

"of, pertaining to, or characterized by adaptation," 1795, from adapt + -ive. The classically proper formation is adaptative (1831).

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adamant (adj.)

late 14c., "hard, unbreakable," from adamant (n.). The figurative sense of "unshakeable" (in belief, etc.) is by 1670s. Related: Adamantly; adamance.

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adage (n.)

"brief, familiar proverb," 1540s, French adage (16c.), from Latin adagium "adage, proverb," apparently a collateral form of adagio, from ad "to" (see ad-) + *agi-, root of aio "I say," which is perhaps cognate with Armenian ar-ac "proverb," asem "to say." But some find this unlikely and suggest the second element might be related to agein "set in motion, drive, urge" (from PIE root *ag- "to drive, draw out or forth, move"). Related: Adagial.

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adamant (n.)

"a very hard stone," mid-14c., adamant, adamaunt, from Old French adamant "diamond; magnet" or directly from Latin adamantem (nominative adamas) "adamant, hardest iron, steel," also used figuratively, of character, from Greek adamas (genitive adamantos), the name of a hypothetical hardest material.

It is a noun use of an adjective meaning "unbreakable, inflexible," which was metaphoric of anything unalterable (such as Hades) and is of uncertain origin. It is perhaps literally "invincible, indomitable," from a- "not" (see a- (3)) + daman "to conquer, to tame," from PIE root *deme- "to constrain, force, break (horses)," for which see tame (adj.). "But semantically, the etymology is rather strange," according to Beekes, who suggests it might be a foreign word altered in Greek by folk etymology, and compares Akkadian (Semitic) adamu.

Applied in antiquity to a metal resembling gold (Plato), white sapphire (Pliny), magnet (Ovid, perhaps through confusion with Latin adamare "to love passionately"), steel, emery stone, and especially diamond, which is a variant of this word. "The name has thus always been of indefinite and fluctuating sense" [Century Dictionary]. The word had been in Old English as aðamans, but the modern word is a re-borrowing.

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pre-adamite (n.)

also preadamite, "one who lived before Adam," 1660s, from pre- + Adam + -ite. Originally in reference to the supposed progenitors of the Gentiles, based on a belief that the biblical Adam was the first parent only of the Jews and their kin.

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adagio (adv.)

c. 1746, in music, "slowly, leisurely and gracefully," Italian, a contraction of ad agio, from ad "to, at" (see ad-) + agio "leisure," from Vulgar Latin *adiacens, present participle of adiacere "to lie at, to lie near" (compare adjacent). In noun sense of "a slow movement," first attested 1784.

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adapter (n.)

1801, "one who adapts (something to something else)," agent noun from adapt. From 1808 as "mechanical means of adapting objects so they fit or work together" (originally of chemistry apparatus); electrical engineering sense is by 1907.

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adaptable (adj.)

1680s, "capable of being made to fit by alteration," from adapt + -able.

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adays (adv.)

late 14c., "by day; on or in the day or time," with adverbial genitive -s from earlier aday (mid-13c.), prepositional phrase used as an adverb, from a- (1) "on, on each" + day (n.). The genitive ending now is regarded as an accusative plural.

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