| hard-nosed(adjective, firm, determined, resolute, obstinate) |
| headstrong(adjective, tough, firm, determined, unreasonable) |
| heroic(adjective, vigorous, noble, resolute, stout) |
| purposeful(adjective, strong, tough, keen, firm) |
| regular(adjective, dull, firm, solid, determined) |
| sedulous |
| set in stone(expression, adjective, idiom, calm, strong) |
| stony(adjective, cold, indifferent, impassive, unyielding) |
| surefooted |
| unhesitating(adjective, complete, firm, certain, serious) |
| unshaken(adjective, clear, strong, flat, firm) |
| unvarying(adjective, calm, strong, secure, firm) |
| valiant(adjective, strong, firm, noble, bold) |
| adamantine(adjective, tough, firm, determined, resolute) |
| allegiant(adjective, close, correct, continue, keen) |
| committed(adjective, kind, keen, warm, firm) |
| confirmed(adjective, certain, determined, usual, steady) |
| continuous(adjective, certain, steady, stable, regular) |
| contrary(adjective, determined, resolute, persistent, obstinate) |
| deep(adjective, clear, tough, severe, determined) |