| inflexible(adjective, person, hard, rough, harsh) |
| remorseless(adjective, mean, severe, harsh, cruel) |
| severe(adjective, person, mean, hard, rough) |
| stony(adjective, person, mean, hard, harsh) |
| uncompromising(adjective, hard, severe, rough, harsh) |
| unyielding(adjective, mean, hard, tough, severe) |
| inhumane(adjective, person, mean, hard, tough) |
| uncharitable(adjective, person, mean, hostile, unkind) |
| unpitying(adjective, mean, severe, harsh, cruel) |
| adamantine(adjective, determined, resolute, uncompromising, unshakeable) |
| intransigent(adjective, determined, resolute, uncompromising, unshakeable) |
| unsparing(adjective, person, mean, severe, harsh) |
| barbaric(adjective, person, pitiless, aroused bad feelings) |
| callous(adjective, person, mean, hard, severe) |
| dog-eat-dog(adjective, mean, hard, severe, harsh) |
| obdurate(adjective, person, mean, hard, rough) |
| tough(adjective, hard, rough, harsh, cruel) |
| vindictive(adjective, mean, hard, tough, severe) |
| bloodthirsty(adjective, severe, harsh, cruel, pitiless) |
| cutthroat(adjective, mean, hard, severe, harsh) |