| untiring(adjective, determined, persevering) |
| dedicated(adjective, strong, firm, total, solid) |
| devoted(adjective, close, strong, correct, firm) |
| persevering(adjective, set, strong, tough, firm) |
| straight(adjective, adverb, close, direct, correct) |
| tireless(adjective, set, strong, firm, determined) |
| dogged(adjective, strong, tough, firm, solid) |
| indefatigable(adjective, set, strong, firm, determined) |
| rigid(adjective, complete, total, intense, determined) |
| stubborn(adjective, strong, tough, firm, intense) |
| immovable(adjective, firm, solid, intense, determined) |
| tenacious(adjective, strong, firm, determined, steady) |
| unshakable |
| undaunted(adjective, determined) |
| unshakeable(adjective, determined, resolute, uncompromising) |
| dependable(adjective, close, correct, firm, honest) |
| intransigent(adjective, determined, resolute, uncompromising, unshakeable) |
| obdurate(adjective, strong, tough, firm, determined) |
| scrupulous(adjective, close, complete, correct, firm) |
| sturdy(adjective, strong, tough, firm, solid) |