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
-
The pose Harris struck and held through her unsuccessful 2024 campaign for the White House is called the good soldier.—
Jeremy Lott,
The Washington Examiner,
3 Oct. 2025
-
Now, after years of mostly unsuccessful efforts to eliminate windows from cabins, one luxury jet maker appears to be on the verge of doing just that.—
Mack DeGeurin,
Popular Science,
2 Oct. 2025
Adjective
-
The rest of the industry wants to emulate this success, but as many editors know, chasing a trend can be a futile endeavor.—
Rebecca Ackermann,
The Atlantic,
5 Oct. 2025
-
At least one company ended the workday early, figuring any attempts to get employees back on track would be futile.—
Kristen Parisi,
Fortune,
2 Oct. 2025
Adjective
-
To overcome the challenge of inefficient routing, Professor Kyung-Joon Park’s team implemented a collective intelligence algorithm based on a human social phenomenon.—
Mrigakshi Dixit,
Interesting Engineering,
30 Sep. 2025
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Without scale, businesses remain inefficient and uncompetitive.—
Emeka Ajene,
semafor.com,
29 Sep. 2025
Adjective
-
But having 10 power play opportunities also made the game somewhat useless.—
Arpon Basu,
New York Times,
1 Oct. 2025
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With her charger useless and the screen showing a dangerously low percentage, the reality sank in.—
Ashley Vega,
PEOPLE,
30 Sep. 2025
Adjective
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In January 2010, a five-day hearing was held in the circuit court to hear testimony about Dassey's motion, much of which focused on evidence that his confession was coerced and that his trial counsel was ineffective.—
Kelli Arseneau,
jsonline.com,
1 Oct. 2025
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The sheer paucity of Russian resources, after three and a half years of war, may lead to a similarly ineffective response to any use of Tomahawks.—
Nick Paton Walsh,
CNN Money,
30 Sep. 2025
Adjective
-
Others—such as an eagerness to engage someone in combat—work in the gym, ring, and battlefield but become counterproductive and even destructive outside of those contexts.—
Dan Brooks,
The Atlantic,
2 Oct. 2025
-
Once again, the process is likely to be costly, counterproductive and completely unnecessary.—
Bloomberg Opinion,
Twin Cities,
25 Sep. 2025
Cite this Entry
“Inefficacious.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/inefficacious. Accessed 7 Oct. 2025.
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