1
as in unsuccessful
not producing the desired result
his efforts to restore the neglected houseplant back to health were belated and sadly inefficacious
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Antonyms & Near Antonyms
2
as in futile
producing no results
an inefficacious medication for a rare form of tuberculosis
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Recent Examples of inefficacious
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
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
Recent Examples of Synonyms for inefficacious
Adjective
-
Attempts to get a comment from the district office were unsuccessful.—
Clifford Ward,
Chicago Tribune,
2 Apr. 2026
-
Corrections staff attempted life-saving measures but were unsuccessful, according to the MDOC.—
Joseph Buczek,
CBS News,
1 Apr. 2026
Adjective
-
But past attempts to achieve similar solutions proved futile.—
Jace Frederick,
Twin Cities,
4 Apr. 2026
-
But the question of what is true or not is futile, even if Calle deliberately provokes this curiosity.—
Elisa Wouk Almino
Editor,
Los Angeles Times,
2 Apr. 2026
Adjective
-
Advocates say the system is not only inefficient but inhumane.—
Jim DeFede,
CBS News,
5 Apr. 2026
-
Seth Lugo salvages inefficient start Lugo didn’t have his best command Saturday.—
Kansas City Star,
Kansas City Star,
4 Apr. 2026
Adjective
-
Bernadine appeared to be useless—or, worse, a potential double agent.—
David D. Kirkpatrick,
New Yorker,
30 Mar. 2026
-
Sending your resume into the void has never felt more useless.—
Catherina Gioino,
Fortune,
23 Mar. 2026
Adjective
-
When the law that governs CARE Court was being written, many advocacy groups insisted that coercion is ineffective and that modern mental health care favors treating people in the least restrictive settings possible.—
Kelly Davis,
San Diego Union-Tribune,
29 Mar. 2026
-
Their navy has been deemed combat ineffective.—
Timothy Nerozzi,
The Washington Examiner,
29 Mar. 2026
Adjective
-
The leaks also led to major changes at Meta and in the tech industry, which began to weed out research that could be viewed as counterproductive for the companies.—
Jonathan Vanian,
CNBC,
29 Mar. 2026
-
These structured habits—doing the same thing in the same place at the same time of day—were more likely to lead to long-term success than attempting to squelch counterproductive impulses in the moment.—
Francine Russo,
Scientific American,
28 Mar. 2026
Cite this Entry
“Inefficacious.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/inefficacious. Accessed 6 Apr. 2026.
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