1
as in unsuccessful
not producing the desired result
his efforts to restore the neglected houseplant back to health were belated and sadly inefficacious
Synonyms & Similar Words
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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
Example Sentences
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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
-
Earlier attempts to develop a commercial market for pecans based on growing trees from seeds had been unsuccessful, as trees originating from seeds have a long lag period until maturation and production of nuts.—
Literary Hub,
Literary Hub,
23 Jan. 2026
-
First responders attempted life-saving measures on EJ, but were unsuccessful.—
Caroline Zimmerman,
Kansas City Star,
22 Jan. 2026
Adjective
-
Their effort to find a home in Overtown seemed futile until Miami-Dade County Commissioner Keon Hardemon, who grew up in Liberty City, conceived a brilliant idea.—
Dorothy Jenkins Fields,
Miami Herald,
9 Jan. 2026
-
But the rally felt less threatening than futile.—
Zach Fisch,
The Atlantic,
6 Jan. 2026
Adjective
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Willingly taking back an inefficient contract from a contender, even if that contract has term involved, is just a more extreme application of this basic logic.—
Thomas Drance,
New York Times,
6 Jan. 2026
-
In processes like this, any loss of carbon as carbon dioxide is a key sign that the underlying process is inefficient.—
Christopher McFadden,
Interesting Engineering,
4 Jan. 2026
Adjective
-
Brown’s statement on Monday was mostly useless corporate-speak.—
Paul Dehner Jr,
New York Times,
6 Jan. 2026
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This tiny amount of copper acts as a molecular steering wheel, preventing sugar molecules from shattering into useless carbon dioxide.—
Aman Tripathi,
Interesting Engineering,
4 Jan. 2026
Adjective
-
The suspect then allegedly stepped towards the officers with the weapon, and officers deployed a Taser and a firearm at the same time, but the Taser was ineffective.—
Adi Guajardo,
CBS News,
8 Jan. 2026
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Combined with sensational media coverage and advocacy by special interests, such studies have led to ineffective or even harmful national health policies.—
Stephen B. Soumerai,
STAT,
7 Jan. 2026
Adjective
-
Short-term fixes alone are unlikely to address the root causes of affordability and, if misguided, could even prove counterproductive.—
Gene Ludwig,
Fortune,
11 Jan. 2026
-
Swart warned the street unrest is actively counterproductive.—
Stepheny Price,
FOXNews.com,
10 Jan. 2026
Cite this Entry
“Inefficacious.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/inefficacious. Accessed 24 Jan. 2026.
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