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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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 new complaint was filed 20 years after Burrowes first claimed in an unsuccessful civil case that Combs may have put out a hit on Shakur and Knight.—
Gina Barton,
USA Today,
7 Sep. 2025
-
All have been unsuccessful due to his status as a suspect in multiple violent crimes.—
Stephanie Nolasco,
FOXNews.com,
6 Sep. 2025
Adjective
-
The Rockies’ brass, however, doesn’t believe the future is futile.—
Patrick Saunders,
Denver Post,
31 Aug. 2025
-
For a company of its size, competing on scale is futile.—
Lela London,
Forbes.com,
30 Aug. 2025
Adjective
-
She’s brought in outside consultants to help the finance office fix its inefficient accounting systems, drawing praise from state officials.—
Rory Linnane,
jsonline.com,
3 Sep. 2025
-
Many cities continue to underprice curbside parking, contributing to congestion, cruising, and inefficient land use.—
Regina Clewlow,
Forbes.com,
2 Sep. 2025
Adjective
-
This method is a significant departure from traditional chemical recycling techniques like pyrolysis, which operate at lower temperatures (450–600°C) and produce over a hundred different by-products, many of which are useless.—
Aman Tripathi,
Interesting Engineering,
3 Sep. 2025
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Economists usually look at new jobs, but immigration is now very low, making that figure useless as a measure of how the economy is doing.—
Bill Conerly,
Forbes.com,
30 Aug. 2025
Adjective
-
After watching their beloved pet struggle, the founder set out to create a solution rooted in clinical research instead of outdated and ineffective formulas.—
Lyssanoel Frater,
USA Today,
3 Sep. 2025
-
In fact, the company deemed its IT-dependent controls relevant to the preparation of the consolidated financial statements were ineffective in 2022 and 2023.—
David Trainer,
Forbes.com,
3 Sep. 2025
Adjective
-
Despite the league's efforts to promote unity, NFL legend Brett Favre feels the messages are counterproductive.—
Ryan Morik,
FOXNews.com,
5 Sep. 2025
-
That’s really so counterproductive.—
Emma Madden,
Pitchfork,
4 Sep. 2025
Cite this Entry
“Inefficacious.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/inefficacious. Accessed 9 Sep. 2025.
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