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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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
-
Barca even took a legal case against the regulations to a Catalan court but were unsuccessful.—
Dermot Corrigan,
New York Times,
19 June 2025
-
Their efforts were unsuccessful, paving the way for Read's retrial this spring.—
Rachel Treisman,
NPR,
18 June 2025
Adjective
-
The researchers said their findings should not suggest afforestation and carbon offsetting are futile.—
Hayley Smith,
Los Angeles Times,
19 June 2025
-
And beneath that fear lies a corrosive belief that resistance is futile.—
Elisa Manfredini,
Time,
14 June 2025
Adjective
-
Windmills, and the rest of this 'JUNK,' are the most expensive and inefficient energy in the world, is destroying the beauty of the environment, and is 10 times more costly than any other energy.—
Adeola Adeosun
Hollie Silverman,
MSNBC Newsweek,
21 June 2025
-
This type of development is inefficient at housing large populations.—
Kristian Fors,
Oc Register,
19 June 2025
Adjective
-
However, disciplined conduct on the part of the activists and the intervention of other bystanders renders the attacks useless.—
Khaleda Rahman,
MSNBC Newsweek,
16 June 2025
-
Pine needles mixed with all the other fine debris rendered the guards useless.—
Tim Carter,
Hartford Courant,
14 June 2025
Adjective
-
Starter James Paxton was immediately hurt and relievers Lucas Sims and Luis Garcia were ineffective and eventually injured.—
Jen McCaffrey,
New York Times,
17 June 2025
-
But while Iran’s regional power projection was diminishing and its arsenal of missiles and drones twice proved largely ineffective, a third concern—a nuclear threat which Israel considered existential—was still growing.—
Ali Vaez,
Time,
14 June 2025
Adjective
-
Beyond that, such dramatic moves could be counterproductive.—
Jeff Cox,
CNBC,
23 June 2025
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Targeting the employers themselves, some of whom Trump relies on for support, would be counterproductive to his agenda, Reisz said.—
Caroline Petrow-Cohen,
Los Angeles Times,
18 June 2025
Cite this Entry
“Inefficacious.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/inefficacious. Accessed 30 Jun. 2025.
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