| ruthless(adjective, hard, tough, severe, cold) |
| thick-skinned(adjective, mean, hard, cool, tough) |
| unenthusiastic(adjective, indifferent, restrained, unfriendly, emotionless) |
| unexcited(adjective, calm, quiet, cool, moderate) |
| unperturbed(adjective, calm, cool, relaxed, detached) |
| untouched(adjective, mean, hard, cool, cold) |
| blank(adjective, cool, detached, sober, unfeeling) |
| blunt(adjective, insensitive) |
| clinical(adjective, detached, dispassionate) |
| cold-hearted(adjective, hard, tough, severe, cold) |
| flat(adjective, calm, dull, cool, tough) |
| guarded |
| impassible(cold, indifferent, unyielding) |
| incurious(adjective, calm, cool, relaxed, cold) |
| inert(adjective, cold, dead, apathy, passive) |
| lethargic(adjective, calm, dull, flat, indifferent) |
| moderate(adjective, calm, quiet, cool, gentle) |
| obtuse(adjective, dull, hard, unfeeling, unsympathetic) |
| placid(adjective, calm, quiet, cool, moderate) |
| self-possessed(adjective, calm, quiet, cool, moderate) |