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
-
Such a vote — which is bound to fail but would put senators on the record — differs from using a simple majority to change the Senate rules, a vote a senator could force after an unsuccessful vote to break a filibuster.—
Burgess Everett,
semafor.com,
19 Mar. 2026
-
After numerous rounds of antibiotics were unsuccessful, a decision was made to euthanize her, according to the zoo.—
Chase Hunter,
Mercury News,
19 Mar. 2026
Adjective
-
Even with the spotlight, Méndez said the debate feels futile.—
Karissa Waddick,
USA Today,
14 Mar. 2026
-
Even subtle futile cycles – processes in which molecules are repeatedly built and broken down – consume energy and generate heat.—
Claudio Villanueva,
The Conversation,
11 Mar. 2026
Adjective
-
Energy-efficient chips Standard computer chips are inefficient.—
Mrigakshi Dixit,
Interesting Engineering,
20 Mar. 2026
-
Yogyakarta is inefficient by modern standards.—
Big Think,
Big Think,
20 Mar. 2026
Adjective
-
The inscription would have sent enemies quite an impression as it was burned into the stone with molten lead, as if daring the attackers to continue their useless advance, Live Science continues.—
Maria Mocerino,
Interesting Engineering,
21 Mar. 2026
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Electronics were useless to her.—
Alex Morris,
Rolling Stone,
19 Mar. 2026
Adjective
-
Arrests have proven to be ineffective at stopping drug use, instead heightening risk of overdose and death.—
Grey Gardner,
Oc Register,
15 Mar. 2026
-
What began as a minor irritation turned into a yearlong medical odyssey marked by the lack of a diagnosis, ineffective treatments, and compounding side effects—all while costs escalated.—
Harvard Business Review,
Harvard Business Review,
11 Mar. 2026
Adjective
-
Tech leaders have quietly backed Anthropic, saying that AI isn’t ready for some weapons and that strong-arming companies is counterproductive and antidemocratic.—
Los Angeles Times,
Los Angeles Times,
20 Mar. 2026
-
That seems to be counterproductive.—
David Remnick,
New Yorker,
13 Mar. 2026
Cite this Entry
“Inefficacious.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/inefficacious. Accessed 23 Mar. 2026.
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