Synonyms|251Antonyms|39|Broader|2Narrower|0Related|383
1
hard-line(adjective, strong, hard, tough, severe)
1
heartless
1
immobile
1
indomitable(adjective, set, strong, hard, tough)
1
inductile
1
inelastic
1
inextensible
1
insensible(adjective, strong, hard, tough, sturdy)
1
invariable
1
iron-willed(adjective, determined, resolute, uncompromising, unshakeable)
1
irreconcilable
1
irremovable
1
lasting
1
marblelike
1
massive
1
mighty
1
nonelastic
1
petrified
1
pitiless
1
potent(adjective, strength)
For more, visit Adamantine on Power Thesaurus
11 years ago|6.5k views|share |citing 
APASmart Define. (2015). adamantine thesaurus. Retrieved September 24, 2026, from https://smartdefine.org/adamantine/thesaurus/synonyms
ChicagoSmart Define. 2015. "adamantine thesaurus" https://smartdefine.org/adamantine/thesaurus/synonyms (accessed September 24, 2026).
HarvardSmart Define 2015, adamantine thesaurus, Smart Define, viewed 24 September, 2026, <https://smartdefine.org/adamantine/thesaurus/synonyms>.
MLASmart Define. "adamantine thesaurus" 10 April 2015. Web. 24 September 2026. <https://smartdefine.org/adamantine/thesaurus/synonyms>