| unassured(adjective, uncertain, nervous, doubtful, shaky) |
| uncertain(adjective, nervous, doubtful, vague, changeable) |
| unclear(adjective, uncertain, nervous, doubtful, unsettled) |
| unconfident(adjective, uncertain, nervous, doubtful, shaky) |
| unconfirmed(doubtful, shaky, vague, hesitant, changeable) |
| unconvinced(adjective, uncertain, nervous, doubtful, shaky) |
| uncounted |
| undependable(adjective, uncertain, nervous, doubtful, shaky) |
| uneasy(shaky, unlikely, unpromising) |
| unestablished |
| unforeseeable(doubtful, vague, hesitant, changeable, unsure) |
| unpredictable(adjective, doubtful, vague, hesitant, changeable) |
| unreliable(adjective, uncertain, nervous, doubtful, vague) |
| unresolved(doubtful, vague, hesitant, changeable, incomplete) |
| unstable(uncertain, nervous, doubtful, shaky, changeable) |
| unsure(adjective, uncertain, nervous, doubtful, vague) |
| untold |
| untrustworthy(adjective, uncertain, nervous, doubtful, shaky) |
| untrusty(adjective, uncertain, nervous, doubtful, shaky) |
| up in the air(expression, idiom, doubtful, vague, hesitant) |