| steadfast(adjective, cold, indifferent, impassive, unyielding) |
| stubborn(adjective, hard, careless, cold, indifferent) |
| unbreakable(adjective, firm, stiff, rigid, unyielding) |
| unconcerned(adjective, mean, hard, cool, unpleasant) |
| unrelenting(adjective, mean, hard, harsh, cruel) |
| blank(adjective, person, hard, feelings, response) |
| bouldered |
| brutal(adjective, mean, hard, tough, severe) |
| craggy(adjective, harsh, coarse, irregular, uneven) |
| detached(adjective, indifferent, unfriendly, unsympathetic, unemotional) |
| emotionless(adjective, cold, indifferent, hostile, unfriendly) |
| implacable(adjective, mean, hard, harsh, cold) |
| indestructible(adjective, firm, rigid, unyielding, steely) |
| inexorable(adjective, mean, hard, harsh, cold) |
| insensible(adjective, mean, hard, tough, severe) |
| pebbly(adjective, rocky, flinty, rock-strewn) |
| remote(adjective, indifferent, unfriendly, unemotional, emotionless) |
| rock-hard(adjective, firm, rigid, unyielding, steely) |
| shingly(adjective, rocky, pebbly, flinty) |
| solid(adjective, hard, firm, stiff, rigid) |