doubtful doubtful /ˈdaʊtfəl/

adjective

1. () Open to doubt or suspicion  ( dubitable , in question , dubious , doubtful )
   open to doubt or suspicion
    The candidate's doubtful past
   the candidate's doubtful past
    He has a dubious record indeed
   he has a dubious record indeed
    What one found uncertain the other found dubious or downright false
   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
   it was more than dubitable whether the friend was as influential as she thought
   
2. () Fraught with uncertainty or doubt  ( doubtful , dubious )
   fraught with uncertainty or doubt
    They were doubtful that the cord would hold
   they were doubtful that the cord would hold
    It was doubtful whether she would be admitted
   it was doubtful whether she would be admitted
    Dubious about agreeing to go
   dubious about agreeing to go
   
3. Unsettled in mind or opinion  ( doubtful , tentative )
   unsettled in mind or opinion
    Drew a few tentative conclusions
   drew a few tentative conclusions