159 entries under rigid topic. ×
| refractory(adjective, hard, strain, rough, harsh) | |
| unwavering(adjective, calm, close, strong, secure) | |
| resistant(adjective, strong, tough, strain, fit) | |
| unshakable(adjective, mean, strong, hard, complete) | |
| solid(adjective, calm, good, close, set) | |
| insistent(adjective, set, determined, steady, resolute) | |
| relentless(adjective, mean, strong, hard, tough) | |
| unrelenting(adjective, mean, strong, hard, tough) | |
| adamant(adjective, mean, strong, hard, secure) | |
| tough(adjective, calm, mean, clear, strong) | |
| obstinate(adjective, mean, strong, hard, tough) | |
| resolved(adjective, set, severe, harsh, certain) | |
| sturdy(adjective, calm, strong, hard, sound) | |
| unbendable(adjective, determined, unreasonable, resolute) | |
| adamantine(adjective, strong, hard, tough, determined) | |
| definite(adjective, good, clear, strong, complete) | |
| dense(adjective, set, strong, hard, tough) | |
| strict(adjective, close, strong, hard, tough) | |
| iron(noun, adjective, mean, strong, hard) | |
| unchangeable(adjective, calm, strong, secure, moderate) |
For more, visit
Firm on
Power Thesaurus
| APA | Smart Define. (2016). firm thesaurus. Retrieved September 25, 2026, from https://smartdefine.org/firm/thesaurus/synonyms |
| Chicago | Smart Define. 2016. "firm thesaurus" https://smartdefine.org/firm/thesaurus/synonyms (accessed September 25, 2026). |
| Harvard | Smart Define 2016, firm thesaurus, Smart Define, viewed 25 September, 2026, <https://smartdefine.org/firm/thesaurus/synonyms>. |
| MLA | Smart Define. "firm thesaurus" 31 March 2016. Web. 25 September 2026. <https://smartdefine.org/firm/thesaurus/synonyms> |