4
unsound(adjective, shaky, uneven, unbalanced, unsteady)
3
absurd(adjective, dubious, improbable)
3
ambivalent(adjective, open, vague, unsure, ambiguous)
3
anxious(adjective, uncertain, awkward, nervous, shy)
3
apprehensive(adjective, uncertain, anxious, awkward, nervous)
3
arbitrary(adjective, changeable, erratic, random)
3
capricious(adjective, dubious, changeable, uneven, unbalanced)
3
cautious
3
confutable
3
contestable
3
crooked
3
cryptic(dark, uncertain, dishonest, vague, dubious)
3
dangerous(noun, adjective, delicate, uncertain, unstable)
3
deniable
3
devious
3
dishonest
3
disturbed(adjective, uncertain, awkward, shy, hesitant)
3
dodgy(adjective, dishonest, dubious, unreliable, suspect)
3
faithless(adjective, uncertain, hesitant, unsure, believing)
3
fallacious(adjective, flimsy)
10 years ago|39k views|share |citing 
APASmart Define. (2016). doubtful thesaurus. Retrieved September 23, 2026, from https://smartdefine.org/doubtful/thesaurus/synonyms
ChicagoSmart Define. 2016. "doubtful thesaurus" https://smartdefine.org/doubtful/thesaurus/synonyms (accessed September 23, 2026).
HarvardSmart Define 2016, doubtful thesaurus, Smart Define, viewed 23 September, 2026, <https://smartdefine.org/doubtful/thesaurus/synonyms>.
MLASmart Define. "doubtful thesaurus" 24 March 2016. Web. 23 September 2026. <https://smartdefine.org/doubtful/thesaurus/synonyms>