Adjective: adamantine ,a-du'man,teen or ,a-du'man,tIn
- Consisting of or having the hardness of adamant
"The adamantine surface of the diamond resisted scratching"
- Having the hardness of a diamond
"The adamantine drill bit could cut through the toughest materials"
- Impervious to pleas, persuasion, requests, reason
"he is adamantine in his refusal to change his mind";
- adamant, inexorable, intransigent, unbudgeable
See also: hard, inflexible
Encyclopedia: Adamantine