7
sophistic(adjective, correct, foolish, true, unreasonable)
7
unconvincing(adjective, poor, inadequate, ineffective, ineffectual)
7
unhealthy(adjective, mean, weak, sick, green)
7
unreasonable(adjective, foolish, fantastic, reasoning, irrational)
7
useless(adjective, void, unsound, trifling, petty)
6
case(noun, disease, subject, patient, casualty)
6
debilitated(adjective, mean, weak, sick, green)
6
frail(adjective, mean, weak, sick, green)
6
illegitimate(adjective, legal)
6
improper(adjective, wrong, fake, counterfeit, dishonest)
6
inaccurate(adjective, wrong, fake, false, counterfeit)
6
sufferer(noun, person, case, subject, patient)
6
victim(noun, case, subject, patient, casualty)
5
convalescent(noun, person, case, subject, patient)
5
impaired(adjective, mean, weak, sick, feeble)
5
inconclusive(adjective, poor, false, unreasonable, inadequate)
5
incongruous(adjective, ill, unhealthy, absurd, irrational)
5
inconsequential(reasoning, irrational, trifling, petty, arbitrary)
5
incurable(noun, person, mean, weak, sick)
5
senseless(adjective, wrong, false, foolish, stupid)
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APASmart Define. (2016). invalid thesaurus. Retrieved September 20, 2026, from https://smartdefine.org/invalid/thesaurus/synonyms
ChicagoSmart Define. 2016. "invalid thesaurus" https://smartdefine.org/invalid/thesaurus/synonyms (accessed September 20, 2026).
HarvardSmart Define 2016, invalid thesaurus, Smart Define, viewed 20 September, 2026, <https://smartdefine.org/invalid/thesaurus/synonyms>.
MLASmart Define. "invalid thesaurus" 29 March 2016. Web. 20 September 2026. <https://smartdefine.org/invalid/thesaurus/synonyms>