| silentious(adjective, close, quiet, restrained, still) |
| smooth(verb, adjective, calm, quiet, subdue) |
| soft(adjective, close, quiet, low, peaceful) |
| soundless(adjective, close, quiet, smooth, soft) |
| sparing(aloof, reserved, reticent, uncommunicative) |
| speechless(adjective, close, quiet, soft, low) |
| stable(adjective, calm, quiet, smooth, tranquil) |
| stagnant(adjective, calm, quiet, smooth, tranquil) |
| static(adjective, calm, quiet, smooth, tranquil) |
| stationary(adjective, calm, quiet, smooth, tranquil) |
| still(verb, adjective, calm, close, quiet) |
| stilled(adjective, close, quiet, soft, low) |
| stock-still(adjective, calm, quiet, smooth, tranquil) |
| struck dumb(verb, expression, adjective, close, quiet) |
| tongue-tied(quiet, still, shy, reticent, silent) |
| tranquil(adjective, calm, quiet, smooth, silent) |
| unclear(still, hushed, soundless) |
| undercover(mysterious, private, reticent, taciturn, uncommunicative) |
| undisturbed(adjective, calm, quiet, smooth, tranquil) |
| unexpressed(adjective, close, quiet, soft, low) |