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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Antonyms & Near Antonyms
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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
-
The handful of lawsuits filed by donor-advisors over how DAF assets are spent or invested have thus far been largely unsuccessful in court.—
Hayley Cuccinello,
CNBC,
26 Feb. 2026
-
Police attempted to forcibly stop the vehicle using spike strips but were unsuccessful.—
Timia Cobb
Breaking News Reporter,
Dallas Morning News,
26 Feb. 2026
Adjective
-
Instigated by the dictatorship invading territories long ago ceded to the English, the war was the new government’s futile attempt to restore a nationalist fantasy of Argentina’s borders (and distract from the country’s collapsing economy).—
Daniel R. Quiles,
Artforum,
1 Mar. 2026
-
These findings don’t mean weight loss is futile; even short-term weight loss correlates with improvements in metabolic health.—
Lori Youmshajekian,
Scientific American,
26 Feb. 2026
Adjective
-
Because of old infrastructure and inefficient temperature-balancing systems, some classrooms get overheated in the winter, even while teachers open windows and run fans.—
Rory Linnane,
jsonline.com,
26 Feb. 2026
-
Even a beautiful kitchen can feel inefficient when it is not organized with intention.—
Jessica Safavimehr,
Southern Living,
25 Feb. 2026
Adjective
-
The big risk for Perplexity, however, is if the models themselves become commodities, rendering useless a service that allows users to switch between the AIs for tasks.—
Rachyl Jones,
semafor.com,
25 Feb. 2026
-
But other people—a lot of other people—will become useless.—
Sam Kriss,
Harpers Magazine,
24 Feb. 2026
Adjective
-
Knoepfler also notes that the same substance that's helpful at one dose might be ineffective or even harmful at another dose.—
Sarah Boden,
NPR,
23 Feb. 2026
-
Using on frozen or too-wet soil will be ineffective, and applying too late allows weeds to germinate.—
Nishaa Sharma,
The Spruce,
22 Feb. 2026
Adjective
-
Strom added that the offering outreach to homeless people with the threat of booting them and throwing their belongings out is counterproductive.—
Josephine Stratman,
New York Daily News,
18 Feb. 2026
-
And data showed outcomes were counterproductive.—
Nick Ferraro,
Twin Cities,
17 Feb. 2026
Cite this Entry
“Inefficacious.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/inefficacious. Accessed 3 Mar. 2026.
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