| serene(adjective, blank, unemotional, emotionless, expressionless) |
| sober(adjective, dull, quiet, set, cool) |
| spiritless(adjective, blank, unemotional, emotionless, expressionless) |
| spiritlessly |
| stony-eyed(adjective, cool, flat, detached, blank) |
| thick-skinned(adjective, cool, detached, blank, sober) |
| toneless(adjective, cool, flat, detached, blank) |
| uncommunicative |
| uncompassionate(adjective, calm, dull, flat, detached) |
| undemonstrative(adjective, calm, dull, cool, flat) |
| unembellished(adjective, tough, rational, straightforward, sober) |
| unemotionally |
| unexcitable(adjective, calm, dull, flat, detached) |
| unfeeling(adjective, calm, dull, cool, tough) |
| unfeelingly |
| unflappable(adjective, calm, blank, unemotional, composed) |
| unidealistic(adjective, tough, rational, straightforward, sober) |
| unimaginative(adjective, tough, rational, straightforward, sober) |
| unimpassioned(adjective, cool, tough, rational, straightforward) |
| unimpressionable(adjective, detached, impassive, unresponsive, laid-back) |