in·​ef·​fi·​ca·​cious | \ (ˌ)i-ˌne-fə-ˈkā-shəs How to pronounce inefficacious (audio) \

Definition of inefficacious

: lacking the power to produce a desired effect : ineffective

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Other Words from inefficacious

inefficaciously adverb
inefficaciousness noun

Examples of inefficacious in a Sentence

his efforts to restore the neglected houseplant back to health were belated and sadly inefficacious an inefficacious medication for a rare form of tuberculosis
Recent Examples on the Web Day — who grew up watching the spelling bee — came up with the concept of exploring the psyche of a winner with an ultimately inefficacious career in 2015 while at a UCB improv sketch-writing class. NBC News, "New film dismantles South Asian stereotypes tied to spelling bee, mental health," 6 Oct. 2020

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

First Known Use of inefficacious

1658, in the meaning defined above

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Time Traveler for inefficacious

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The first known use of inefficacious was in 1658

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Cite this Entry

“Inefficacious.” Dictionary, Merriam-Webster, Accessed 9 May. 2021.

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