in·​ef·​fi·​ca·​cy | \ (ˌ)i-ˈne-fi-kə-sē How to pronounce inefficacy (audio) \

Definition of inefficacy

: lack of power to produce a desired effect

Examples of inefficacy in a Sentence

Recent Examples on the Web All this inefficacy belies a deeper problem with our education system. Daniel Buck, National Review, 30 Oct. 2021 The most common challenges for organizations today include high carbon emissions, finite fossil-fuel availability, severe weather issues causing service disruptions, water scarcity, inefficacy and waste management. Ashish Saxena, Forbes, 8 Oct. 2021 Phil Jackson took over the team the next year, ushering in a new period of inefficacy for the team. New York Times, 20 Oct. 2021 As feelings of cynicism, inefficacy and exhaustion increase, naturally, joy starts to dwindle across most if not all areas of life. Rachel Montañez, Forbes, 24 June 2021 The potential side effects or inefficacy of the drug are immaterial compared to that outcome. Wired Staff, Wired, 5 Apr. 2020 President Trump is reportedly frustrated with the seeming inefficacy of U.S. efforts to force Maduro out. Ishaan Tharoor, Washington Post, 25 Feb. 2020 Not long ago, some were pretending in public as though Trump was a capable world leader, all the while taking notes or recording conversations for a book that would tell the true story of his inefficacy. Dahleen Glanton,, 27 Nov. 2019 She and Kanuri discussed the inefficacy of earplugs and the pros and cons of analog versus digital white-noise machines. Bianca Bosker, The Atlantic, 8 Oct. 2019 See More

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'inefficacy.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of inefficacy

circa 1615, in the meaning defined above

History and Etymology for inefficacy

Late Latin inefficacia, from Latin inefficac-, inefficax inefficacious, from in- + efficac-, efficax efficacious

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Time Traveler for inefficacy

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The first known use of inefficacy was circa 1615

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Cite this Entry

“Inefficacy.” Dictionary, Merriam-Webster, Accessed 26 May. 2022.

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