| uncommunicative(adjective, person, quiet, soft, low) |
| unsociable(adjective, person, quiet, avoid, still) |
| buttoned up(expression, adjective, close, quiet, still) |
| bashful(quiet, still, silent, hushed) |
| clammed up(expression, adjective, close, quiet, restrained) |
| closemouthed(quiet, soft, low, reticent) |
| hushed(adjective, close, quiet, soft, low) |
| muted(quiet, soft, low, reticent) |
| nonvocal(adjective, close, quiet, soft, low) |
| not forthcoming(expression, quiet, silent, tight-lipped) |
| quiet(soft, low, still, reticent) |
| silent(adjective, quiet, soft, low, still) |
| soundless(quiet, soft, low, still) |
| tongue-tied(quiet, still, reticent, silent) |
| unspeaking(adjective, close, quiet, restrained, still) |
| voiceless(quiet, soft, low, still) |
| wordless(adjective, close, quiet, soft, low) |
| zipped(quiet, still, reticent, silent) |