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Synonyms for Doubtful (same or very similar meaning)

WordNet sense 1 (unsettled in mind or opinion):
tentative

WordNet sense 2 (still in doubt):
unsettled

WordNet sense 3 (open to doubt or suspicion):
dubious, dubitable

WordNet sense 4 (subject to question):
questionable

WordNet sense 5 (lacking or indicating lack of confidence or assurance):
uncertain, unsure


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