| aloof(adjective, cool, correct, cold, shy) |
| austere(adjective, strong, hard, tough, severe) |
| business-minded |
| decided(adjective, firm, certain, determined, limited) |
| formal(adjective, correct, cold, detached, unfriendly) |
| hardened(adjective, hard, firm, solid, careless) |
| iron-willed(adjective, determined, resolute, uncompromising, unshakeable) |
| loyal(adjective, strong, firm, determined, bold) |
| persevering(adjective, strong, tough, flat, firm) |
| pitiless(adjective, severe, harsh, cruel, determined) |
| puritanical(adjective, severe) |
| resistant(adjective, hard, firm, determined, resolute) |
| rock-ribbed(adjective, determined, resolute, uncompromising, unshakeable) |
| solid(adjective, hard, firm, stiff, tense) |
| stark(adjective, hard, severe, firm, solid) |
| strong(adjective, close, hard, tough, flat) |
| true(adjective, strong, direct, flat, firm) |
| unfeeling(adjective, hard, tough, severe, harsh) |
| unforgiving(adjective, hard, rough, harsh, cruel) |
| unmoved(adjective, unyielding, unreceptive) |