Synonyms|215Antonyms|56|Broader|0Narrower|0Related|93
1
inoperable(wild, unreasonable, useless, absurd, abstract)
1
insignificant
1
insufficient(adjective, inutility)
1
inutile(adjective, inutility)
1
invalid
1
irrelevant
1
ivory-tower(wild, unreasonable, useless, absurd, abstract)
1
lightweight
1
manque
1
neutralized(adjective, inferior, inadequate, limited, feeble)
1
no-account
1
no avail(adjective, arouse bad feelings)
1
no can do(weak, skill, inadequate, unfit, inept)
1
no go(expression, wild, unreasonable, inadequate, feeble)
1
no good(weak, skill, inadequate, unfit, inept)
1
no purpose(adjective, arouse bad feelings)
1
non-beneficial(adjective, ability, proficiency, efficiency, effectiveness)
1
nonfunctional(wild, unreasonable, useless, absurd, abstract)
1
nonviable(wild, unreasonable, useless, absurd, abstract)
1
not able(weak, skill, inadequate, unfit, inept)
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HarvardSmart Define 2016, inefficacious thesaurus, Smart Define, viewed 24 September, 2026, <https://smartdefine.org/inefficacious/thesaurus/synonyms>.
MLASmart Define. "inefficacious thesaurus" 24 March 2016. Web. 24 September 2026. <https://smartdefine.org/inefficacious/thesaurus/synonyms>