as in effectiveness
the power to produce a desired result
questioned the efficacy of the alarms in actually preventing auto theft
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Recent Examples of efficacy
The efficacy of the joint survey and its response rates, the league argued, were compromised by multiple surveys covering similar topics.
—
Michael McCann, Sportico.com, 13 Feb. 2026
Further testing in lab experiments and clinical trials will be needed to confirm the efficacy of such a drug.
—Khloe Quill, FOXNews.com, 12 Feb. 2026
Maybe the speed of the infection had something to do with the efficacy of the cure?
—Kathryn Vanarendonk, Vulture, 11 Feb. 2026
Zepbound’s higher efficacy has been a key factor in driving more patients and prescribers away from choosing Wegovy, which has shown around 15% weight loss on average in clinical trials.
—Annika Kim Constantino, CNBC, 11 Feb. 2026
See All Example Sentences for efficacy
Michael McCann, Sportico.com, 13 Feb. 2026
Further testing in lab experiments and clinical trials will be needed to confirm the efficacy of such a drug.
—Khloe Quill, FOXNews.com, 12 Feb. 2026
Maybe the speed of the infection had something to do with the efficacy of the cure?
—Kathryn Vanarendonk, Vulture, 11 Feb. 2026
Zepbound’s higher efficacy has been a key factor in driving more patients and prescribers away from choosing Wegovy, which has shown around 15% weight loss on average in clinical trials.
—Annika Kim Constantino, CNBC, 11 Feb. 2026
See All Example Sentences for efficacy
Recent Examples of Synonyms for efficacy
Noun
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But internal documents produced in the discovery phase of the social media litigation raise questions about Meta’s focus on teen users and the effectiveness of its safety features.—
Clare Duffy,
CNN Money,
17 Feb. 2026
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Although its effectiveness as a cure-all hasn’t been entirely confirmed by science, there are a few significant reasons to consider trying this bitter-tasting tea.—
PubSubHub User,
Chicago Tribune,
16 Feb. 2026
Noun
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Future work will focus on scaling the process for potential industrial use and improving recovery efficiency.—
Neetika Walter,
Interesting Engineering,
20 Feb. 2026
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The public would see more information about how judges rule on pretrial matters, sentencing, courtroom efficiency and how often their decisions are reversed on appeal under this House bill.—
Stephen Gruber-Miller,
Des Moines Register,
20 Feb. 2026
Cite this Entry
“Efficacy.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/efficacy. Accessed 21 Feb. 2026.
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