Inefficacious

Synonyms for "inefficacious" (46 found)

Ranked by relevance and common usage.

Closest matches (10)

abortive barren bootless counterproductive effete empty failed failing fatuous featherweight

Strong matches (13)

feckless forceless fruitless futile impotent inadequate inane ineffective ineffectual

Adjective(4 words)

fruitless futile ineffective ineffectual

Related words (23)

inefficient inoperative invalid lame lightweight manque meaningless no account nugatory null powerless sterile stillborn unauthoritative unavailing unfortunate unsturdy unsuccessful useless vain

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Adjective(2 words)

Related word relations

OpenGloss and ConceptNet supply richer edges like generalizations, collocations, and derivations.

6 relation types

Antonyms

1 entries

Synonyms

1 entries

derived

2 entries

inefficaciously inefficaciousness

derived from

1 entries

related to

3 entries

consequence effective ineffectual

similar

3 entries

ineffective ineffectual uneffective

Translations

2 translations across 1 languages.

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Bulgarian

2 entries

неефективен adj (Incapable of having the intended consequence)
неефикасен adj (Incapable of having the intended consequence)

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Data sourced from Wiktionary, WordNet, CMU, and other open linguistic databases. Updated March 2026.