Definition of 'adamantine'

Adjective

1. consisting of or having the hardness of adamant
2. having the hardness of a diamond
3. impervious to pleas, persuasion, requests, reason; "he is adamant in his refusal to change his mind"; "Cynthia was inexorable; she would have none of him"- W.Churchill; "an intransigent conservative opposed to every liberal tendency"
      Synonyms: adamant inexorable intransigent

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