Synonyms:
doubtful, dubious, dubitable, in_question(p)
Meaning: 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
Synonyms:
doubtful, dubious
Meaning: 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"
Usage examples
Noakes looked doubtful.
Don't walk in doubtful paths.
'I thought you seemed a little doubtful.'
This is at least doubtful, if not more than that.
I have been doubtful, troubled, almost distracted.
Doubtful, considering that she was entirely by herself.
This would leave one thousand doubtful ones to win over.
To me it seems at least doubtful that he possesses anything at all."
And that he is alive at all is doubtful, for his trips do not tire him.
Is it doubtful that this would lead to extravagance, if not to corruption?