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
Our study suggests that one way to increase the enrollment of women into clinical trials, and to ensure that equal standards of safety and efficacy apply to men and women, is to have more women scientists lead those trials.
—
Harsh Gupta, Time, 16 Oct. 2025
The tool is considered a must-have deterrent when venturing into bear country, though questions remain about its efficacy compared to firearms in fending off charging bears.
—Owen Clarke, Outside, 15 Oct. 2025
Esfandyar-pour said the platform could deepen understanding of cancer mechanisms and improve predictive accuracy in drug efficacy assessments.
—Aamir Khollam, Interesting Engineering, 15 Oct. 2025
Each disease requires trials to show efficacy of treatment to the FDA.
—Noah Lyons, San Diego Union-Tribune, 15 Oct. 2025
See All Example Sentences for efficacy
Harsh Gupta, Time, 16 Oct. 2025
The tool is considered a must-have deterrent when venturing into bear country, though questions remain about its efficacy compared to firearms in fending off charging bears.
—Owen Clarke, Outside, 15 Oct. 2025
Esfandyar-pour said the platform could deepen understanding of cancer mechanisms and improve predictive accuracy in drug efficacy assessments.
—Aamir Khollam, Interesting Engineering, 15 Oct. 2025
Each disease requires trials to show efficacy of treatment to the FDA.
—Noah Lyons, San Diego Union-Tribune, 15 Oct. 2025
See All Example Sentences for efficacy
Recent Examples of Synonyms for efficacy
Noun
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Theetge will be on leave pending an internal investigation on the effectiveness of her leadership, according to a release from the city manager.—
David Ferrara,
Cincinnati Enquirer,
20 Oct. 2025
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Tester notes highlight the blanket’s ease of use and effectiveness.—
Brigitt Earley,
Glamour,
20 Oct. 2025
Noun
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Its compact design, combined with a high-efficiency 800W motor and intelligent three-speed control, is built to navigate city streets with ease.—
Matt Emma,
USA Today,
24 Oct. 2025
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The e-note has octa-core processing brains supported by 6 GB of RAM and 64 GB of storage, with microSD expansion and cloud sync available for workflow efficiency.—
New Atlas,
New Atlas,
24 Oct. 2025
Cite this Entry
“Efficacy.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/efficacy. Accessed 27 Oct. 2025.
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