| hard-hearted(adjective, mean, hard, harsh, stubborn) |
| inalterable(adjective, set, certain, limited, definite) |
| narrow(adjective, hard, moderate, rough, firm) |
| puritanical(adjective, severe) |
| ruthless(adjective, hard, rough, harsh, cruel) |
| true(adjective, strong, smooth, tough, flat) |
| uncharitable(adjective, hateful, impatient, prejudiced, fanatical) |
| unresponsive(adjective, person, hard, careless, indifferent) |
| unshaken |
| unsparing(adjective, strong, hard, tough, severe) |
| bullheaded(adjective, strong, hard, tough, firm) |
| changeless(adjective, set, certain, limited, definite) |
| cold(adjective, strong, hard, severe, harsh) |
| conventional(adjective, moderate, stiff, cautious, timid) |
| decided(adjective, firm, certain, resolution, limited) |
| definite(adjective, strong, hard, severe, flat) |
| formal(adjective, strong, severe, fixed, serious) |
| frozen(adjective, hard, firm, solid, stiff) |
| gritty(resolution, hardness, rocky, pebbly, flinty) |
| hard-core(adjective, strong, hard, tough, severe) |