6
ineligible(adjective, weak, inadequate, useless, incompetent)
6
insufficient(adjective, weak, inadequate, useless, incompetent)
5
inapt(adjective, suitable, incompetent, impotence)
4
futile(adjective, weak, inferior, inadequate, limited)
4
improper(adjective, dull, flat, slow, awkward)
4
incapacitated(adjective, weak, skill, inadequate, useless)
4
not able(expression, adjective, idiom, skill, talent)
4
not up to(expression, adjective, idiom, weak, skill)
4
unapt(adjective, useless, incompetent, unfit, unqualified)
4
untalented(adjective, awkward, inept, educated, overall)
4
worthless(adjective, inferior, inadequate, limited, feeble)
3
faulty(adjective, useless, unfit)
3
impuissant(adjective, skill, talent, inept, powerless)
3
inappropriate(adjective, dull, flat, slow, awkward)
3
inefficacious(adjective, skill, inferior, inadequate, limited)
3
inoperative(adjective, skill, inferior, inadequate, limited)
3
maladroit(adjective, dull, flat, slow, inadequate)
3
not equal to(expression, adjective, idiom, weak, skill)
3
poor(adjective, weak, inadequate, unfit, unqualified)
3
talentless(adjective, educated, overall, well-informed)
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APASmart Define. (2016). unable thesaurus. Retrieved September 21, 2026, from https://smartdefine.org/unable/thesaurus/synonyms
ChicagoSmart Define. 2016. "unable thesaurus" https://smartdefine.org/unable/thesaurus/synonyms (accessed September 21, 2026).
HarvardSmart Define 2016, unable thesaurus, Smart Define, viewed 21 September, 2026, <https://smartdefine.org/unable/thesaurus/synonyms>.
MLASmart Define. "unable thesaurus" 29 March 2016. Web. 21 September 2026. <https://smartdefine.org/unable/thesaurus/synonyms>