| restrained(still, reticent, silent, hushed, uncommunicative) |
| retiring(adjective, person, avoid, asocial, dissocial) |
| self contained |
| shut-in(adjective, person, avoid, asocial, dissocial) |
| silent(adjective, quiet, soft, low, still) |
| silentious(adjective, close, quiet, restrained, still) |
| soundless(quiet, soft, low, still, shy) |
| still(quiet, soft, low, silent, hushed) |
| struck dumb(expression, adjective, close, quiet, restrained) |
| tongue-tied(quiet, still, shy, reticent, silent) |
| unapproachable |
| unclear(quiet, soft, low, still, hushed) |
| unclubbable |
| unheard(still, hushed, soundless) |
| unspeaking(adjective, close, quiet, restrained, still) |
| voiceless(quiet, soft, low, still, shy) |
| wordless(adjective, close, quiet, soft, low) |
| zipped(quiet, still, shy, reticent, silent) |
| laconic(still, hushed, soundless) |
| confidentiality(adjective, hushed, wordless) |