| nonchalant(adjective, blank, unemotional, emotionless, expressionless) |
| passionless(adjective, calm, dull, flat, detached) |
| phlegmatic(adjective, calm, tough, rational, straightforward) |
| reserved(adjective, cool, detached, blank, sober) |
| stoical(adjective, blank, unemotional, emotionless, expressionless) |
| unconcerned(adjective, calm, cold, blank, aloof) |
| unreadable(adjective, ambiguous, expressionless, unfathomable, enigmatic) |
| vacuous |
| along for the ride(expression, adjective, idiom, calm, dull) |
| anesthesia |
| arcane(adjective, sharp, difficult, hidden, ironic) |
| blah(adjective, calm, dull, flat, detached) |
| callous(adjective, detached, blank, impassive, unemotional) |
| calm(adjective, cool, tough, rational, straightforward) |
| cold-blooded(adjective, cool, tough, rational, straightforward) |
| cold-bloodedly |
| cold fish(expression, adjective, cool, flat, detached) |
| coldhearted(adjective, detached, impassive, unresponsive, laid-back) |
| coldheartedly |
| coldly |