inefficacious

adjective

in·​ef·​fi·​ca·​cious (ˌ)i-ˌne-fə-ˈkā-shəs How to pronounce inefficacious (audio)
: lacking the power to produce a desired effect : ineffective
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
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Most wore inefficacious cloth masks, too. James Lileks, National Review, 25 Aug. 2022 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, 6 Oct. 2020

Word History

First Known Use

1658, in the meaning defined above

Time Traveler
The first known use of inefficacious was in 1658

Dictionary Entries Near inefficacious

Cite this Entry

“Inefficacious.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/inefficacious. Accessed 15 Dec. 2024.

Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!