| indifferent(adjective, calm, cool, relaxed, cold) |
| indurate(adjective, mean, hard, tough, harsh) |
| indurated(adjective, cool, blank, aloof, unemotional) |
| inexcitable(adjective, cool, blank, aloof, unemotional) |
| inexorable(adjective, mean, hard, tough, harsh) |
| inexpressive(adjective, cool, blank, aloof, unemotional) |
| inflexible(adjective, mean, hard, harsh, stubborn) |
| inscrutable(adjective, cool, blank, aloof, unemotional) |
| insensible(adjective, cool, indifferent, blank, aloof) |
| insentient |
| insouciant(adjective, calm, cool, relaxed, detached) |
| iron(adjective, mean, hard, tough, harsh) |
| laid back(expression, adjective, calm, cool, relaxed) |
| light(adjective, calm, cool, relaxed, detached) |
| loose(adjective, calm, cool, relaxed, detached) |
| matter-of-fact(adjective, cool, blank, aloof, unemotional) |
| mean(adjective, hard, tough, harsh, unfeeling) |
| mulish(adjective, mean, hard, harsh, inflexible) |
| neglectful(adjective, calm, cool, relaxed, detached) |
| negligent(adjective, calm, cool, relaxed, detached) |