| senseless(adjective, hard, tough, severe, cold) |
| set in stone(expression, adjective, idiom, mean, hard) |
| severe(adjective, calm, hard, tough, harsh) |
| solitary(adjective, indifferent, detached, distant, remote) |
| standoffish(adjective, indifferent, detached, distant, remote) |
| steady(adjective, calm, restrained, unconcerned, subdued) |
| stiff-necked(adjective, mean, hard, tough, harsh) |
| stony(adjective, hard, tough, severe, cruel) |
| stony-eyed(adjective, cool, flat, detached, blank) |
| stuck up(expression, adjective, indifferent, detached, distant) |
| supercilious(adjective, indifferent, detached, distant, remote) |
| surly(adjective, hard, tough, severe, cold) |
| toneless(adjective, cool, flat, detached, blank) |
| tough(adjective, mean, hard, severe, harsh) |
| tough nut to crack(expression, adjective, idiom, mean, hard) |
| unaffected(adjective, detached, blank, unfeeling, impassive) |
| unaltered(adjective, calm, restrained, unconcerned, subdued) |
| unamiable(adjective, hard, tough, severe, cold) |
| unapproachable(adjective, indifferent, detached, distant, remote) |
| unbending(adjective, mean, hard, harsh, inflexible) |