| passive(adjective, insensitive) |
| pat(adjective, determined, resolute, uncompromising, unshakeable) |
| persistent(determined, usual, fixed, stubborn, established) |
| pertinacious(adjective, determined, fixed, resolute, stubborn) |
| perverse(adjective, determined, fixed, resolute, stubborn) |
| pigheaded(adjective, determined, fixed, resolute, stubborn) |
| proof against(verb, phrasal verb, insensibility) |
| pugnacious |
| reprobate(adjective, rude, corrupt, wicked, immoral) |
| resistant(adjective, strong, hard, tough, fit) |
| rocklike(adjective, firm, stiff, rigid) |
| rough(adjective, person, hard, fit, feelings) |
| rugged(adjective, strong, fit, healthy, well) |
| sclerotic |
| seared |
| self-opinionated(adjective, determined, resolute, uncompromising, unshakeable) |
| self-willed(adjective, determined, fixed, resolute, stubborn) |
| severe(adjective, hard, tough, cruel, unsympathetic) |
| sophisticated(skilled, experienced, mature, urbane, seasoned) |
| stale |