- granitic, granitelike, rocklike, stony - hard as granite; "a granitic fist"
Antonym: soft (indirect, via hard)
- flinty, granitic, unyielding - having austere inflexibility; "a flinty manner"; "granitic morality"; "his unyielding mouth and glassy eyes"- Marchette Chute
Antonym: flexible (indirect, via inflexible)