| strong-willed(adjective, determined, resolute, unshakeable) |
| hard-line(adjective, tough, firm, difficult, rigid) |
| hardheaded(adjective, determined, resolute, obstinate, unshakeable) |
| pigheaded(adjective, mean, hard, firm, deliberate) |
| unchangeable(adjective, complete, secure, certain, true) |
| bigoted(adjective, determined, resolute, obstinate, unshakeable) |
| brassbound(adjective, resist, determined, resolute, persistent) |
| bull-headed(adjective, determined, resolute, obstinate, stubborn) |
| die-hard(adjective, resist, determined, resolute, persistent) |
| difficult(tough, rough, harsh, obstinate, stubborn) |
| peremptory(adjective, severity, authoritative, overbearing) |
| persistent(adjective, tough, firm, deliberate, determined) |
| ruthless(adjective, hard, rough, harsh, cruel) |
| sturdy |
| unforgiving(adjective, hard, severe, rough, harsh) |
| unswerving(adjective, determined, resolute, unshakeable) |
| blunt(adjective, severe) |
| cruel(adjective, hard, severe, rough, harsh) |
| decided(adjective, clear, firm, certain, definite) |
| dour(adjective, severe, severity) |