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
Dietary supplements aren’t evaluated for safety and efficacy by the U.S. Food and Drug Administration (FDA) like prescription and over-the-counter medications are.
—
Tom Gavin, EverydayHealth.com, 28 July 2025
More than 100 scientific studies across decades have looked at the efficacy and safety of the pair and all of them have found the drugs safe for use, according to an analysis from The New York Times.
—The Hill, 23 July 2025
Graham, Todd and Gibbs — their efficacy — will go a long way toward determining the ceiling for KU’s defense this fall.
—Shreyas Laddha, Kansas City Star, 23 July 2025
Extract every efficacy endpoint, its p-value, confidence interval, and sample size.
—Christiaan Hetzner, Fortune, 15 July 2025
See All Example Sentences for efficacy
Tom Gavin, EverydayHealth.com, 28 July 2025
More than 100 scientific studies across decades have looked at the efficacy and safety of the pair and all of them have found the drugs safe for use, according to an analysis from The New York Times.
—The Hill, 23 July 2025
Graham, Todd and Gibbs — their efficacy — will go a long way toward determining the ceiling for KU’s defense this fall.
—Shreyas Laddha, Kansas City Star, 23 July 2025
Extract every efficacy endpoint, its p-value, confidence interval, and sample size.
—Christiaan Hetzner, Fortune, 15 July 2025
See All Example Sentences for efficacy
Recent Examples of Synonyms for efficacy
efficiency
Noun
-
You are not designed for speed, efficiency, and convenience.—
Pia Lauritzen,
Forbes.com,
20 July 2025
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Elsewhere The Langham engages in several meaningful efficiency efforts, including the use of low-wattage LED lighting; linen reuse for guests who opt out of daily refreshes; low-flow water fixtures; and various recycling efforts, including a program for fryer oil.—
Paul Brady,
Travel + Leisure,
19 July 2025
Cite this Entry
“Efficacy.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/efficacy. Accessed 4 Aug. 2025.
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