| tongueless(adjective, speak, silent, voiceless, aphony) |
| dull(verb, adjective, calm, quiet, reduce) |
| soften(verb, dull, quiet, increase, restrain) |
| tongue-tied(adjective, quiet, awkward, still, reticent) |
| reserved(adjective, close, quiet, soft, low) |
| suppress(verb, calm, dull, quiet, restrain) |
| tight-lipped(adjective, close, quiet, soft, low) |
| noiseless(adjective, close, quiet, soft, low) |
| uncommunicative(adjective, close, quiet, soft, low) |
| aphonic(adjective, speak, silent, dazed, dumb) |
| gag(verb, calm, dull, quiet, suppress) |
| tacit |
| tame(verb, increase, discipline, train, pacify) |
| moderate(verb, dull, increase, reduce, diminish) |
| muzzle(verb, calm, dull, quiet, suppress) |
| quieten(verb, calm, dull, quiet, diminish) |
| smother(verb, dull, quiet, diminish, impair) |
| soundless(adjective, close, quiet, soft, low) |
| unsaid |
| soft-pedal(verb, calm, dull, quiet, suppress) |