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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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
-
Life-saving measures were unsuccessful.—
Forum News Service,
Twin Cities,
9 Apr. 2026
-
During the most recent campaign and in a previous unsuccessful run for mayor, Laesch claimed Irvin prioritized government contracts or incentives to those who donated to his campaign, which Irvin consistently denied.—
R. Christian Smith,
Chicago Tribune,
8 Apr. 2026
Adjective
-
But past attempts to achieve similar solutions proved futile.—
Jace Frederick,
Twin Cities,
4 Apr. 2026
-
But the question of what is true or not is futile, even if Calle deliberately provokes this curiosity.—
Elisa Wouk Almino
Editor,
Los Angeles Times,
2 Apr. 2026
Adjective
-
Advocates say the system is not only inefficient but inhumane.—
Jim DeFede,
CBS News,
5 Apr. 2026
-
Seth Lugo salvages inefficient start Lugo didn’t have his best command Saturday.—
Kansas City Star,
Kansas City Star,
4 Apr. 2026
Adjective
-
Architects and other critics of the project had panned the staircase as too large and basically useless since there was no way to enter the ballroom at the top.—
Darlene Superville,
Los Angeles Times,
2 Apr. 2026
-
In practice, this means a madhouse of multimedia rooms, packed with gurgling videos and useless machines and humanoid bodies.—
Zachary Fine,
New Yorker,
31 Mar. 2026
Adjective
-
The foursome was similarly ineffective keeping Betts from getting to her spots, unable to deter lobs over the top of post-ups in isolation.—
Sabreena Merchant,
New York Times,
6 Apr. 2026
-
During the pandemic, compounders charged exorbitant prices for ivermectin, even after the drug proved ineffective against COVID-19.—
Dhruv Khullar,
New Yorker,
6 Apr. 2026
Adjective
-
The leaks also led to major changes at Meta and in the tech industry, which began to weed out research that could be viewed as counterproductive for the companies.—
Jonathan Vanian,
CNBC,
29 Mar. 2026
-
These structured habits—doing the same thing in the same place at the same time of day—were more likely to lead to long-term success than attempting to squelch counterproductive impulses in the moment.—
Francine Russo,
Scientific American,
28 Mar. 2026
Cite this Entry
“Inefficacious.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/inefficacious. Accessed 13 Apr. 2026.
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