| hardened(adjective, hard, tough, severe, cruel) |
| heartless(adjective, hard, tough, severe, cruel) |
| icy(adjective, hard, tough, severe, cold) |
| inanimate(adjective, hard, tough, severe, cold) |
| inhuman(adjective, hard, tough, severe, cold) |
| insensate(adjective, hard, tough, severe, cold) |
| insensible(adjective, hard, tough, severe, cold) |
| insensitive(adjective, hard, tough, severe, cold) |
| iron-hearted(adjective, hard, tough, severe, cold) |
| merciless(adjective, hard, tough, severe, cold) |
| numb(adjective, hard, tough, severe, cold) |
| numbed(adjective, unfeeling, frozen, deadened) |
| obdurate(adjective, hard, tough, severe, cold) |
| pitiless(adjective, hard, tough, severe, cold) |
| ruthless(adjective, hard, tough, severe, cold) |
| senseless(adjective, hard, tough, severe, cold) |
| severe(adjective, hard, tough, cold, cruel) |
| stony(adjective, hard, tough, severe, cruel) |
| surly(adjective, hard, tough, severe, cold) |
| thick-skinned(adjective, hard, tough, severe, cruel) |