| peaceable(adjective, calm, quiet, serene) |
| unemotional(adjective, quiet, cool, moderate, gentle) |
| unflappable(adjective, calm, quiet, cool, moderate) |
| unworried(adjective, feature, state, calm, quiet) |
| dispassionate(adjective, calm, quiet, cool, smooth) |
| insouciant(adjective, feature, state, calm, indifferent) |
| phlegmatic(adjective, calm, smooth, indifferent, still) |
| temperate(adjective, calm, quiet, light, cool) |
| apathetic(adjective, indifferent, nonchalant, undaunted, unworried) |
| casual(adjective, feature, state, trait) |
| laid-back(adjective, feature, state, calm, quiet) |
| light(adjective, feature, state, calm, quiet) |
| motionless(adjective, calm, quiet, cool, smooth) |
| self-controlled |
| silent(adjective, calm, quiet, smooth, tranquil) |
| sober(adjective, calm, easy, relaxed, comfortable) |
| sound(noun, verb, adjective, firm, whole) |
| stolid |
| undemanding(adjective, feature, state, calm, quiet) |
| unmolested |