Synonyms of dubious

Adjective

1. doubtful, dubious, uncertain (vs. certain), unsure (vs. sure), incertain

usage: 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"

2. doubtful, dubious, dubitable, in question(predicate), questionable (vs. unquestionable)

usage: 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"- Karen Horney

3. dubious, unconvinced (vs. convinced)

usage: not convinced; "they admitted the force of my argument but remained dubious"

Definition and meaning of dubious (Dictionary)