| low-pitched(adjective, close, quiet, soft) |
| muffled(adjective, close, quiet, soft) |
| mute(adjective, close, quiet, soft) |
| noiseless(adjective, close, quiet, soft) |
| not saying boo(expression, adjective, idiom, close, quiet) |
| quieted(adjective, close, quiet, soft) |
| soundless(adjective, close, quiet, soft) |
| speechless(adjective, close, quiet, soft) |
| still(adjective, close, quiet, soft) |
| stilled(adjective, close, quiet, soft) |
| taciturn(adjective, close, quiet, soft) |
| tight-lipped(adjective, close, quiet, soft) |
| uncommunicative(adjective, close, quiet, soft) |
| unexpressed(adjective, close, quiet, soft) |
| unspeaking(adjective, close, quiet, soft) |
| unuttered(adjective, close, quiet, soft) |
| whist(adjective, close, quiet, soft) |