307 entries under adjective topic. ×

4
unavailing
4
unfavorable
4
unfounded(wrong, fake, false, counterfeit)
4
unpleasant
4
unscientific(reasoning, worthless, unfounded)
4
unusable(useless, unfit, inapplicable)
4
vain(void, unsound, trifling, petty)
3
absurd(foolish, unreasonable, fantastic, absurd)
3
annulled
3
baseless(foolish, unreasonable, worthless, unacceptable)
3
bootless
3
crazy(foolish, unreasonable, absurd, illogical)
3
foolish(unreasonable, fantastic, absurd, irrational)
3
futile
3
handicapped(poor, inadequate, ineffective, ineffectual)
3
helpless(incompetent, vulnerable, incapable)
3
ill-suited(bad, useless, unfit)
3
implausible(poor, false, unreasonable, inadequate)
3
impracticable(useless, unfit, inapplicable)
3
in poor health(expression, idiom, mean, sick)
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APASmart Define. (2016). invalid thesaurus. Retrieved September 23, 2026, from https://smartdefine.org/invalid/thesaurus/synonyms
ChicagoSmart Define. 2016. "invalid thesaurus" https://smartdefine.org/invalid/thesaurus/synonyms (accessed September 23, 2026).
HarvardSmart Define 2016, invalid thesaurus, Smart Define, viewed 23 September, 2026, <https://smartdefine.org/invalid/thesaurus/synonyms>.
MLASmart Define. "invalid thesaurus" 29 March 2016. Web. 23 September 2026. <https://smartdefine.org/invalid/thesaurus/synonyms>