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 now separatist success will largely depend on whether the movement serves the interests of a dominant power, not on its legitimacy or efficacy.
—
Ryan D. Griffiths, Foreign Affairs, 20 May 2025
The Essence is truly a powerhouse product that channels nutrients into the skin and boosts the efficacy of your skin care ritual, all while working to keep your skin hydrated, plump, and glowing.
—Ariana Yaptangco, Glamour, 19 May 2025
But early reports from China, where authorities were physically sealing off apartment buildings, were encouraging about the efficacy of such tactics.
—Daniel Immerwahr, New Yorker, 19 May 2025
More than 100 scientific studies have been conducted to examine the safety and efficacy of using mifepristone and misoprostol to end a pregnancy.
—Alejandra O’Connell-Domenech, The Hill, 19 May 2025
See All Example Sentences for efficacy
Ryan D. Griffiths, Foreign Affairs, 20 May 2025
The Essence is truly a powerhouse product that channels nutrients into the skin and boosts the efficacy of your skin care ritual, all while working to keep your skin hydrated, plump, and glowing.
—Ariana Yaptangco, Glamour, 19 May 2025
But early reports from China, where authorities were physically sealing off apartment buildings, were encouraging about the efficacy of such tactics.
—Daniel Immerwahr, New Yorker, 19 May 2025
More than 100 scientific studies have been conducted to examine the safety and efficacy of using mifepristone and misoprostol to end a pregnancy.
—Alejandra O’Connell-Domenech, The Hill, 19 May 2025
See All Example Sentences for efficacy
Recent Examples of Synonyms for efficacy
efficiency
Noun
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Modern practices can not only improve efficiency and compliance but also open doors to strategic opportunities that drive growth and resilience.—
Gary Galstyan,
Forbes.com,
21 May 2025
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From Weeks 1-13, the Lions ranked top-10 in scoring defense (2nd), yards per game allowed (10th), rushing yards per game allowed (fifth), goal-to-go efficiency (third), red-zone efficiency (second), third-down conversion rate (1st), defensive success rate (sixth) and defensive EPA/play (second).—
Colton Pouncy,
New York Times,
21 May 2025
Cite this Entry
“Efficacy.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/efficacy. Accessed 5 Jun. 2025.
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