| sullen |
| timid(adjective, quiet, cool, cold, sensitive) |
| timorous(adjective, quiet, restrained, humble, shy) |
| unaffable(adjective, reticent, unassuming, undemonstrative, self-effacing) |
| unapproachable(cool, cold, sensitive, shy, unfriendly) |
| unassertive(adjective, reticent, unassuming, undemonstrative, self-effacing) |
| unbending(adjective, cool, cold, sensitive, shy) |
| undemonstrative(adjective, quiet, restrained, shy, thoughtful) |
| unexpansive(adjective, reticent, unassuming, undemonstrative, self-effacing) |
| unforthcoming(adjective, quiet, cool, cold, restrained) |
| unfrequented |
| ungregarious |
| unneighborly(adjective, cool, cold, sensitive, shy) |
| uppity(adjective, cool, cold, sensitive, shy) |
| autistic |
| aloof(quiet, shy, thoughtful, unfriendly, antisocial) |
| antisocial(shy, unfriendly) |
| aseptic(adjective, quiet, restrained, detached, thoughtful) |
| casual(quiet, detached, thoughtful, shrinking, inhibited) |
| cold(shy, unfriendly, reserved, antisocial) |