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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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
-
Neighbors attempted to rescue her but were unsuccessful, the sheriff’s office said.—
Nour Rahal,
Freep.com,
5 Aug. 2025
-
The current governor of Virginia, Glenn Youngkin, is a close ally of Trump, frequently appearing on the 2024 campaign trail with the then-candidate amid a push to try to flip Virginia red, which was unsuccessful yet yielded a close race.—
Zach LaChance,
The Washington Examiner,
4 Aug. 2025
Adjective
-
Attempts by deputies and paramedics to revive him were futile, and he was pronounced dead at 4:40 p.m.—
Kelly Davis,
San Diego Union-Tribune,
5 Aug. 2025
-
Mexico later crashed out in the group stage, proving that hope is futile, but Ochoa’s class is timeless.—
The Athletic UK Staff,
New York Times,
23 July 2025
Adjective
-
There were two other good starts in there as well, but over his last three, he’s been inefficient at best and uncompetitive at worst.—
Abbey Mastracco,
New York Daily News,
4 Aug. 2025
-
Extracting plant dyes, whittling a spoon, making felt—these projects are inefficient and, Ginn argues, extremely satisfying.—
Sophia Stewart,
The Atlantic,
1 Aug. 2025
Adjective
-
Infrastructure is useless without operators who can manage it.—
Expert Panel®,
Forbes.com,
5 Aug. 2025
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The deals typically provide revenue for the host community while enabling the solar industry to cover essentially useless land with solar panels rather than taking out-of-service farmland, open fields or similar space.—
Don Stacom,
Hartford Courant,
5 Aug. 2025
Adjective
-
This process is largely ineffective at temperatures under 18,000 degrees Fahrenheit (10,000 degrees Celsius).—
Perri Thaler,
Space.com,
16 Aug. 2025
-
That’s where the sandwich comes in — a mockery of the military presence, so obviously ineffective that it was supposed to make the whole situation look stupid.—
David Weigel,
semafor.com,
15 Aug. 2025
Adjective
-
This can be counterproductive for long-term weight management, as muscle loss can lower the number of calories burned at rest.—
Sarah Jividen,
Verywell Health,
29 July 2025
-
Observers have noted that closing the Strait of Hormuz would be counterproductive for Iran, which relies on the waterway to get its own oil to customers, mostly in China.—
Matt Egan,
CNN Money,
24 June 2025
Cite this Entry
“Inefficacious.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/inefficacious. Accessed 20 Aug. 2025.
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