| moderate(adjective, calm, dull, weak, soft) |
| muffled(adjective, dull, close, quiet, weak) |
| musical |
| mute(adjective, close, quiet, soft, low) |
| muted(adjective, calm, dull, close, quiet) |
| noiseless(adjective, close, quiet, soft, low) |
| not saying boo(expression, adjective, idiom, close, quiet) |
| quiescent(adjective, close, quiet, soft, low) |
| quieted(adjective, close, quiet, soft, low) |
| reserved(adjective, close, quiet, soft, low) |
| reticent(adjective, close, quiet, soft, low) |
| secretive(adjective, close, quiet, soft, low) |
| sepulchral |
| silent(adjective, close, quiet, soft, gentle) |
| slight(adjective, calm, dull, weak, soft) |
| smooth(adjective, calm, dull, weak, soft) |
| softened(adjective, dull, quiet, weak, soft) |
| soothing(adjective, calm, dull, weak, soft) |
| soundless(adjective, close, quiet, soft, low) |
| speechless(adjective, close, quiet, soft, low) |