adamantine
adjective
- of or like adamant; very hard, as dental enamel; unbreakable
- unyielding; firm
See adamantine in American Heritage Dictionary 4
(ădˌə-mănˈtēnˌ, -tīnˌ, -tĭn)
adjective- Made of or resembling adamant.
- Having the hardness or luster of a diamond.
- Unyielding; inflexible: “If there is one dominant trait that emerges from this account, it is adamantine willpower” (Eugene Linden).
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