12
precarious(adjective, uncertainty, uncertain, unreliable, insecure)
12
shaky(adjective, uncertain, doubtful, dubious, unreliable)
12
vague(adjective, clear, rough, uncertain, anxious)
11
ambiguous(adjective, clear, rough, certain, uncertain)
11
unsettled(noun, adjective, open, rough, uncertain)
10
problematical(adjective, clear, certain, uncertain, dubious)
10
fly-by-night(adjective, uncertain, dishonest, doubtful, deceitful)
10
incredible(adjective, great, flat, poor, extraordinary)
10
unlikely(adjective, open, uncertain, doubtful, shaky)
9
indefinite(adjective, obscure, rough, uncertain, doubtful)
9
notorious
9
slippery(adjective, uncertainty, dishonest, deceitful, unreliable)
9
unbelievable(adjective, weak, great, flat, poor)
9
undecided(noun, adjective, uncertain, doubtful, unsettled)
9
undependable(adjective, uncertain, dishonest, doubtful, deceitful)
8
confutable
8
dubitable(adjective, clear, certain, uncertain, anxious)
8
queer(adjective, unusual, strange, odd, dubious)
8
refutable
8
shifty(adjective, corrupt, dishonest, deceitful, dubious)
11 years ago|31k views|share |citing 
APASmart Define. (2015). questionable thesaurus. Retrieved September 20, 2026, from https://smartdefine.org/questionable/thesaurus/synonyms
ChicagoSmart Define. 2015. "questionable thesaurus" https://smartdefine.org/questionable/thesaurus/synonyms (accessed September 20, 2026).
HarvardSmart Define 2015, questionable thesaurus, Smart Define, viewed 20 September, 2026, <https://smartdefine.org/questionable/thesaurus/synonyms>.
MLASmart Define. "questionable thesaurus" 13 April 2015. Web. 20 September 2026. <https://smartdefine.org/questionable/thesaurus/synonyms>