ad·a·mant (ădə-mənt, -mănt′)
Not willing to change one's opinion, purpose, or principles; unyielding.
1. A stone once believed to be impenetrable in its hardness.
2. An extremely hard substance.
[From Middle English, a hard precious stone, from Old French adamaunt, from Latin adamās, adamant-, from Greek, unconquerable, hard steel, diamond; see demə- in the Appendix of Indo-European roots.]
ada·mance, ada·man·cy n.
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