3
hypothetical
3
ill-founded
3
inconclusive
3
inconsiderate
3
reckless
3
suppositional
3
tenuous(adjective, poor, negative, implausible, vacant)
3
uncorroborated
3
unproved(adjective, reasoning)
3
unproven
3
unprovoked(adjective, reason, senseless, unwarranted, reckless)
3
unsubstantial(adjective, error, unsubstantiality)
3
unsupportable(adjective, senseless, unwarranted, wanton, gratuitous)
3
unverified
3
without foundation(expression, adjective, idiom, unsubstantiality)
2
crazy(foolish, unreasonable, illogical)
2
faulty
2
flawed
2
foolish(adjective, unreasonable, illogical)
2
foundationless(adjective, reason, false, unwarranted, untrue)
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APASmart Define. (2015). groundless thesaurus. Retrieved September 20, 2026, from https://smartdefine.org/groundless/thesaurus/synonyms
ChicagoSmart Define. 2015. "groundless thesaurus" https://smartdefine.org/groundless/thesaurus/synonyms (accessed September 20, 2026).
HarvardSmart Define 2015, groundless thesaurus, Smart Define, viewed 20 September, 2026, <https://smartdefine.org/groundless/thesaurus/synonyms>.
MLASmart Define. "groundless thesaurus" 14 April 2015. Web. 20 September 2026. <https://smartdefine.org/groundless/thesaurus/synonyms>