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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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
-
Investigators said that an initial PIT maneuver was unsuccessful, but a second one caused the truck to crash into another vehicle and roll over onto its side – an incident that was caught on home surveillance video.—
CBS News,
CBS News,
14 May 2026
-
Jeremy Brandon Johnson, 53, of Eveleth, was pronounced dead at the scene after lifesaving measures were unsuccessful.—
Forum News Service,
Twin Cities,
14 May 2026
Adjective
-
But this story has a happier, less futile ending.—
Deborah Treisman,
New Yorker,
17 May 2026
-
To complain about cramps was futile.—
Nami Mun,
The Atlantic,
16 May 2026
Adjective
-
Although this might seem inefficient for a bird of their size, inside a rainforest, long soaring wings would actually be more of a liability than an asset.—
Scott Travers,
Forbes.com,
17 May 2026
-
In their final seasons, the critique extends to AI’s temptations and shortcomings, ultimately making the case for the inefficient art of comedy.—
Caroline Framke,
The Atlantic,
14 May 2026
Adjective
-
In other words, Greg had thought insomnia a problem of the rich, the weak, the useless, the indulgent, the lazy.—
Weike Wang,
New Yorker,
17 May 2026
-
But those GPUs are useless without the memory chips stacked alongside them, and Samsung’s three fabrication complexes in South Korea are among the most important pieces of the AI industrial boom.—
Catherina Gioino,
Fortune,
17 May 2026
Adjective
-
That strategy is becoming ineffective.—
Raheel Sheikh,
Forbes.com,
18 May 2026
-
Suspensions One Kansas City food business was suspended due to ineffective pest control measures.—
Joseph Hernandez,
Kansas City Star,
16 May 2026
Adjective
-
That assumption is both outdated and counterproductive.—
Adam Goodcoff,
STAT,
13 May 2026
-
However foolhardy, counterproductive and costly, cities have a right to challenge state laws.—
The Editorial Board,
Oc Register,
13 May 2026
Cite this Entry
“Inefficacious.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/inefficacious. Accessed 22 May. 2026.
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