| hard(adjective, mean, cool, unpleasant, cold) |
| harsh(adjective, mean, hard, cool, unpleasant) |
| heartless(adjective, mean, hard, cool, unpleasant) |
| hesitating(adjective, weak, uncertain, doubtful, hesitant) |
| hot-and-cold(adjective, weak, uncertain, doubtful, hesitant) |
| impassible(adjective, temper, cold, negative, behave) |
| incurious(adjective, cold, dead, apathy, passive) |
| ineffective |
| ineffectual |
| infirm of purpose(expression, idiom) |
| infirm of will(expression, idiom) |
| inhuman(adjective, temper, cold, negative, behave) |
| insentient(adjective, cold, dead, apathy, passive) |
| insouciant(adjective, cold, dead, apathy, passive) |
| lacking interest |
| lackluster(adjective, enthusiasm) |
| laodicean(adjective, cold, dead, apathy, passive) |
| lifeless(adjective, dull, weak, warm, bland) |
| lily-livered |
| limp(adjective, dull, weak, mild, careless) |