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
Which Works Better for Pain? The results of a comparative study show no significant difference in the efficacy of Vicodin and Percocet for musculoskeletal pain treatment in adults.
—
Ayesha Gulzar, Verywell Health, 3 Jan. 2025
While additional clinical trials are needed to understand the efficacy of astaxanthin on depressive symptoms in humans, initial studies in mice have been promising.
—Amiah Taylor, Discover Magazine, 25 Dec. 2024
Expectations around its efficacy just need to be kept in check—something that can be hard to do when everybody on social media is praising a technique.
—Fiorella Valdesolo, Vogue, 20 Dec. 2024
Tylenol has more than 60 years of clinical use to support its safety and efficacy.
—Benedict Cosgrove, Newsweek, 20 Dec. 2024
See all Example Sentences for efficacy 
Ayesha Gulzar, Verywell Health, 3 Jan. 2025
While additional clinical trials are needed to understand the efficacy of astaxanthin on depressive symptoms in humans, initial studies in mice have been promising.
—Amiah Taylor, Discover Magazine, 25 Dec. 2024
Expectations around its efficacy just need to be kept in check—something that can be hard to do when everybody on social media is praising a technique.
—Fiorella Valdesolo, Vogue, 20 Dec. 2024
Tylenol has more than 60 years of clinical use to support its safety and efficacy.
—Benedict Cosgrove, Newsweek, 20 Dec. 2024
See all Example Sentences for efficacy
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Cite this Entry
“Efficacy.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/efficacy. Accessed 22 Jan. 2025.
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