1
sophistic(adjective, mad, unreasonable, irrational, fallacious)
1
sophistical(bad, false, mad, unreasonable, irrational)
1
superstitious
1
tenuous(poor, negative, implausible, vacant, unconvincing)
1
uncorroborated
1
unjustifiable(adjective, unwarranted)
1
unreasonable(poor, mad, irrational, unnecessary, implausible)
1
unreasoned(mad, unreasonable, irrational)
1
unsatisfactory(bad, poor, false, incorrect, inaccurate)
1
unsound(adjective, error)
1
unsubstantial(error, unsubstantiality)
1
unsubstantiated
1
unsupported
1
unsustained
1
untenable
1
untrue(adjective, error)
1
vain
1
way off(expression, mad, unreasonable, irrational)
1
without basis
1
without foundation(expression, idiom, unsubstantiality)
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APASmart Define. (2015). ungrounded thesaurus. Retrieved September 20, 2026, from https://smartdefine.org/ungrounded/thesaurus/synonyms
ChicagoSmart Define. 2015. "ungrounded thesaurus" https://smartdefine.org/ungrounded/thesaurus/synonyms (accessed September 20, 2026).
HarvardSmart Define 2015, ungrounded thesaurus, Smart Define, viewed 20 September, 2026, <https://smartdefine.org/ungrounded/thesaurus/synonyms>.
MLASmart Define. "ungrounded thesaurus" 14 April 2015. Web. 20 September 2026. <https://smartdefine.org/ungrounded/thesaurus/synonyms>