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
But oxytocin nasal sprays aren’t ready for prime time because more research needs to be done to determine efficacy, the right context or conditions for using it, and how to control the dosage, Che said.
—
The Washington Post, San Diego Union-Tribune, 5 Aug. 2025
The members also expressed skepticism around the safety and efficacy of the COVID-19 vaccine, which Kennedy announced earlier this year will no longer be recommended for healthy children and healthy pregnant women.
—Mary Kekatos, ABC News, 31 July 2025
Compounded drugs are not reviewed for safety and efficacy by the FDA.
—Anjeanette Damon, ProPublica, 30 July 2025
Children: There is a lack of research on the safety and efficacy of this treatment in children.
—Anna Giorgi, Verywell Health, 29 July 2025
See All Example Sentences for efficacy
The Washington Post, San Diego Union-Tribune, 5 Aug. 2025
The members also expressed skepticism around the safety and efficacy of the COVID-19 vaccine, which Kennedy announced earlier this year will no longer be recommended for healthy children and healthy pregnant women.
—Mary Kekatos, ABC News, 31 July 2025
Compounded drugs are not reviewed for safety and efficacy by the FDA.
—Anjeanette Damon, ProPublica, 30 July 2025
Children: There is a lack of research on the safety and efficacy of this treatment in children.
—Anna Giorgi, Verywell Health, 29 July 2025
See All Example Sentences for efficacy
Recent Examples of Synonyms for efficacy
efficiency
Noun
-
Manufacturing innovation has historically followed a familiar arc: point solutions to fix discrete issues, application-level changes to improve efficiency, and system-level breakthroughs such as the assembly line.—
Forbes.com,
Forbes.com,
13 Aug. 2025
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But another College Football Playoff appearance hinges on quarterback Maddux Madsen’s efficiency as the focal point of the offense in the post-Ashton Jeanty era.—
Jon Wilner,
Mercury News,
13 Aug. 2025
Cite this Entry
“Efficacy.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/efficacy. Accessed 19 Aug. 2025.
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