Doubtful or not settled in opinion; being in doubt; wavering or fluctuating; undetermined.
source: Webster 1913
adjective satellite
fraught with uncertainty or doubt
They were doubtful that the cord would hold. It was doubtful whether she would be admitted. Dubious about agreeing to go.
source: WordNet 3.0
open to doubt or suspicion
The candidate's doubtful past. He has a dubious record indeed. What one found uncertain the other found dubious or downright false. It was more than dubitable whether the friend was as influential as she thought.
source: WordNet 3.0
not convinced
They admitted the force of my argument but remained dubious.
