doubtful
1. [ adjective ] open to doubt or suspicion
Synonyms: dubious in_question dubitable
Examples:

"the candidate's doubtful past" "he has a dubious record indeed" "what one found uncertain the other found dubious or false" "it was more than dubitable whether the friend was as influential as she thought"- Karen Horney

Related terms: questionable
2. [ adjective ] fraught with uncertainty or doubt
Synonyms: dubious
Examples:

"they were doubtful that the cord would hold" "it was doubtful whether she would be admitted" "dubious about agreeing to go"

Related terms: uncertain
3. [ adjective ] unsettled in mind or opinion
Synonyms: tentative
Examples:

"drew a few tentative conclusions"

Related terms: unsettled
Similar spelling:   doubtfully