modified
Ambiguous
Uncertain in mind
Of questionable character
doubtful implies strong uncertainty as to the probability, value, honesty, validity, etc. of something a doubtful remedy; dubious is less strong, suggesting merely vague suspicion or hesitancy dubious about the future; questionable strictly suggests only that there is some reason for doubt, but it is often used as a euphemism to imply strong suspicion, almost amounting to certainty, of immorality, dishonesty, etc. a questionable reputation; problematic implies only uncertainty with no suggestion of a moral question a problematic success
See doubtful in Webster's New World Roget's A-Z Thesaurus II
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