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

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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