Efficacy antonyms

What is the opposite word for Efficacy?

Antonyms for efficacy
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E F I L P U W
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Efficacy Thesaurus
Definitions of Efficacy
Efficacy Synonyms
Nearby Words
efficiency, efficacious, efficient, efficaciousness, efficaciously
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Opposite words of efficacy
Image search results for Efficacy
ability, competence, aptitude ability, competence, aptitude ability, competence, aptitude ability, competence, aptitude ability, competence, aptitude
Cite this Source
Antonyms for Efficacy. (2016). Retrieved 2026, August 14, from https://thesaurus.plus/antonyms/efficacy
Antonyms for Efficacy. N.p., 2016. Web. 14 Aug. 2026. <https://thesaurus.plus/antonyms/efficacy>.
Antonyms for Efficacy. 2016. Accessed August 14, 2026. https://thesaurus.plus/antonyms/efficacy.