9
unsubstantiated(adjective, unwarranted, untrue, flimsy, questionable)
5
unconfirmed(adjective, unwarranted, untrue, flimsy, unsubstantiated)
5
unsupported
4
groundless(adjective, unwarranted, untrue, flimsy, unsubstantiated)
4
unfounded(adjective, unwarranted, untrue, flimsy, unsubstantiated)
4
unproven(adjective, unsubstantiated, unconfirmed)
3
baseless(adjective, substantiation)
3
unofficial(adjective, unauthorized)
2
not proved(expression, idiom)
2
unverified(adjective, unsubstantiated, unconfirmed)
2
unwarranted(adjective, untrue, flimsy, unsubstantiated, unfounded)
1
apocryphal
1
bottomless(adjective, unwarranted, untrue, flimsy, unsubstantiated)
1
doubtful(adjective, unsubstantiated, unconfirmed)
1
flimsy(adjective, unwarranted, untrue, unsubstantiated, unfounded)
1
foundationless(adjective, unwarranted, untrue, flimsy, unsubstantiated)
1
gratuitous(adjective, unwarranted, untrue, flimsy, unsubstantiated)
1
hard to believe(expression, adjective, idiom, unsubstantiated, unconfirmed)
1
inconclusive
1
indecisive
11 years ago|681 views|share |citing 
APASmart Define. (2015). uncorroborated thesaurus. Retrieved September 21, 2026, from https://smartdefine.org/uncorroborated/thesaurus/synonyms
ChicagoSmart Define. 2015. "uncorroborated thesaurus" https://smartdefine.org/uncorroborated/thesaurus/synonyms (accessed September 21, 2026).
HarvardSmart Define 2015, uncorroborated thesaurus, Smart Define, viewed 21 September, 2026, <https://smartdefine.org/uncorroborated/thesaurus/synonyms>.
MLASmart Define. "uncorroborated thesaurus" 14 April 2015. Web. 21 September 2026. <https://smartdefine.org/uncorroborated/thesaurus/synonyms>