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adamant

[ad-uh-muhnt, -mant]
adjective
  1. utterly unyielding in attitude or opinion in spite of all appeals, urgings, etc.
  2. too hard to cut, break, or pierce.
noun
  1. any impenetrably or unyieldingly hard substance.
  2. a legendary stone of impenetrable hardness, formerly sometimes identified with the diamond.

Origin of adamant

before 900; Middle English < Old French adamaunt < Latin adamant- (stem of adamas) hard metal (perhaps steel), diamond < Greek, equivalent to a- a-6 + -damant- verbal adjective of damân to tame, conquer; replacing Old English athamans (< Medieval Latin) and Middle English aymont < Middle French aimant < Vulgar Latin *adimant- < Latin
Related formsad·a·man·cy [ad-uh-muhn-see] /ˈæd ə mən si/, ad·a·mance, nounad·a·mant·ly, adverbun·ad·a·mant, adjective

Synonyms for adamant

1. inflexible, rigid, uncompromising.

Antonyms for adamant

1. flexible, easygoing, yielding.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for adamance

adamant

adjective
  1. unshakable in purpose, determination, or opinion; unyielding
  2. a less common word for adamantine (def. 1)
noun
  1. any extremely hard or apparently unbreakable substance
  2. a legendary stone said to be impenetrable, often identified with the diamond or loadstone
Derived Formsadamantly, adverb

Word Origin for adamant

Old English: from Latin adamant-, stem of adamas, from Greek; literal meaning perhaps: unconquerable, from a- 1 + daman to tame, conquer
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
Word Origin and History for adamance

adamant

n.

mid-14c., from Old French adamant and directly from Latin adamantem (nominative adamas) "adamant, hardest iron, steel," also figuratively, of character, from Greek adamas (genitive adamantos) "unbreakable, inflexible" metaphoric of anything unalterable, also the name of a hypothetical hardest material, perhaps literally "invincible," from a- "not" + daman "to conquer, to tame" (see tame (adj.)), or else a word of foreign origin altered to conform to Greek.

Applied in antiquity to white sapphire, magnet (perhaps via confusion with Latin adamare "to love passionately"), steel, emery stone, and especially diamond (see diamond). The word was in Old English as aðamans "a very hard stone."

adamant

adj.

late 14c., "hard, unbreakable," from adamant (n.). Figurative sense of "unshakeable" first recorded 1670s. Related: Adamantly; adamance.

Online Etymology Dictionary, © 2010 Douglas Harper