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 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,, "Column: Former staffers keep writing books about how inept Donald Trump is. We shouldn’t buy books from cowards.," 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, "Why Everything Is Getting Louder," 8 Oct. 2019 As Luther’s claims about the inefficacy of indulgences spread, with help from the new Gutenberg printing press, so did the idea of the solas, which formed the basis of the Reformation. Jamie Quatro, The New Yorker, "The Hidden Life of a Forgotten Sixteenth-Century Female Poet," 5 Aug. 2019 Due to corruption and bureaucratic inefficacy, nations in the Northern Triangle collect less in tax revenues than most other Latin American countries (relative to the size of each nation’s gross domestic product). Eric Levitz, Daily Intelligencer, "We Owe Central American Migrants Much More Than This," 21 June 2018 Several candidates for state office seized the findings as an opportunity to call for a total disbanding and replacement of the ethics commission, which has for years been dogged by accusations of inefficacy and bias. Vivian Wang, New York Times, "Ex-Cuomo Aide Is Cleared by State Panel of Sexual Harassment and Assault," 11 June 2018 Kelly will inherit a West Wing that has set a new standard for chaos, backstabbing, factionalism, and inefficacy. David A. Graham, The Atlantic, "Can John Kelly Stop the Chaos Inside Trump's West Wing?," 28 July 2017 The inefficacy of Obama’s administration implementing protection for undocumented immigrants should also be highlighted. Mario Nicolais, The Denver Post, "DACA put in peril — by two administrations," 14 Jan. 2017 The giraffe, said Mivart, was a perfect example of natural selection’s inefficacy. Brian Switek, WIRED, "OpenLab Finalist: Giraffes – Necks for food, or necks for sex?," 7 Jan. 2011

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.

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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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The first known use of inefficacy was circa 1615

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Cite this Entry

“Inefficacy.” Dictionary, Merriam-Webster, Accessed 21 Feb. 2020.

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