doubtful

Short definition from Wiktionary

Adjective

1. 1
   Subject to, or causing doubt.
2. 2
   Experiencing or showing doubt, skeptical.
3. 3
   Undecided or of uncertain outcome.
4. 4
   Fearsome, dreadful.
5. 5
   Improbable or unlikely.
6. 6
   Suspicious, or of dubious character.
7. 7
   Unclear or unreliable.

Noun

1. 1
   A doubtful person or thing.