| inconversable(adjective, close, quiet, restrained, still) |
| indistinct(still, hushed, soundless) |
| indrawn |
| inhibited(still, hushed, soundless) |
| insociable(adjective, person, avoid, asocial, dissocial) |
| lane |
| lone |
| morose |
| mousy(still, hushed, soundless) |
| mum(adjective, quiet, soft, low, still) |
| mute(quiet, soft, low, still, reticent) |
| muted(quiet, soft, low, shy, reticent) |
| noiseless(quiet, soft, low, still, hushed) |
| noncontact(adjective, person, avoid, asocial, dissocial) |
| noncontacting(adjective, person, avoid, asocial, dissocial) |
| nonsocial(adjective, person, avoid, asocial, dissocial) |
| nonvocal(adjective, close, quiet, soft, low) |
| not forthcoming(expression, quiet, shy, silent, tight-lipped) |
| quiet(soft, low, still, shy, reticent) |
| quiet speechless(expression, still, hushed, soundless) |