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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Antonyms & Near Antonyms
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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
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More than a decade ago, her association sought the same change at the federal level and was unsuccessful — opposed at the time by Wine Institute.
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The city had taken it over, but several attempts at renovation were unsuccessful, until Alan Leventhal, chief executive of Beacon Capital Partners, happened to see the building and envisioned it as a great hotel.
Adjective
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Fahd, cradling his bloodied baby, pressing his hand to Sam’s head in a futile attempt to staunch the bleeding.
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The suit recounts the rapid deterioration — and futile attempts to salvage — what for a long time had been a mutually beneficial professional and artistic partnership.
Adjective
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Looking back a half-decade from now, today’s AI systems will seem laughably resource-intensive and inefficient.
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This process was time-consuming, inefficient, and vulnerable to human judgment.
Adjective
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Using that quartet in what is essentially a useless game would be playing with fire.
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Maps had become useless; streets and landmarks washed away or hidden.
Adjective
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Conventional interventions have been largely ineffective, suggesting a rate increase may be the strongest tool left for policymakers to stabilize the won.
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While some viral health trends are harmless—or simply ineffective—others can put your health at serious risk.
Adjective
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The idea of ever getting comfortable or confident is almost counterproductive.
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Doing so while having to perform in games where the results are all that matter can be confounding and even counterproductive.
Cite this Entry
“Inefficacious.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/inefficacious. Accessed 26 Jun. 2026.
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