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 study also evaluates the efficacy of atropine eye drops in slowing myopia in children.
—
Oc Register, 9 Sep. 2025
Various media reports also suggest that the vaccine has shown 100 percent efficacy in preclinical trials, although Newsweek has been unable to verify this claim.
—Hannah Millington, MSNBC Newsweek, 8 Sep. 2025
Her legal team has filed multiple appeals to dismiss them to varying degrees of efficacy.
—Allison P. Davis, Vulture, 8 Sep. 2025
Early data about the efficacy of a medicine that targets the underlying cause of FSHD has been promising, and further research is underway.
—Kate Wolffe, Sacbee.com, 7 Sep. 2025
See All Example Sentences for efficacy
Oc Register, 9 Sep. 2025
Various media reports also suggest that the vaccine has shown 100 percent efficacy in preclinical trials, although Newsweek has been unable to verify this claim.
—Hannah Millington, MSNBC Newsweek, 8 Sep. 2025
Her legal team has filed multiple appeals to dismiss them to varying degrees of efficacy.
—Allison P. Davis, Vulture, 8 Sep. 2025
Early data about the efficacy of a medicine that targets the underlying cause of FSHD has been promising, and further research is underway.
—Kate Wolffe, Sacbee.com, 7 Sep. 2025
See All Example Sentences for efficacy
Recent Examples of Synonyms for efficacy
Noun
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Element Human, which uses behavioral AI to measure creative effectiveness, analyzed a recent Jake collaboration with creator Daniel LaBelle.—
Jamie Gutfreund,
Forbes.com,
15 Sep. 2025
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Injection wells could also help reduce Arizona’s carbon footprint through carbon capture, though some scientists question that technology’s effectiveness.—
Austin Corona,
AZCentral.com,
15 Sep. 2025
Noun
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At the same time, novel current routing allows for maximum magnetic flux cancellation, contributing to the power module’s clean, low-loss electrical output—in other words, its ultrahigh efficiency, according to a press release.—
Prabhat Ranjan Mishra,
Interesting Engineering,
13 Sep. 2025
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At Google scale, efficiency was essential.—
Matthew Kayser,
USA Today,
13 Sep. 2025
Cite this Entry
“Efficacy.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/efficacy. Accessed 17 Sep. 2025.
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