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
The authors examined the safety and efficacy of once-daily orforglipron at doses of 6, 12 or 36 mg, compared with a placebo group, alongside a healthy diet and physical activity for 72 weeks.
—
Hannah Millington, MSNBC Newsweek, 17 Sep. 2025
Issue clear, accessible guidance to pharmacists, health care providers, and to the public about the safety and efficacy of COVID-19 vaccines.
—Kristen Jordan Shamus, Freep.com, 17 Sep. 2025
Kennedy has also questioned the safety and efficacy of mRNA vaccines, the technology that was used to develop the most effective COVID vaccines.
—Swapna Venugopal Ramaswamy, USA Today, 17 Sep. 2025
Note that abrasive brushes or sponges will leave small scratches on the surface, but, unlike with a nonstick pan, the scratches won’t damage the pan’s long-term efficacy.
—Emily Johnson, Bon Appetit Magazine, 15 Sep. 2025
See All Example Sentences for efficacy
Hannah Millington, MSNBC Newsweek, 17 Sep. 2025
Issue clear, accessible guidance to pharmacists, health care providers, and to the public about the safety and efficacy of COVID-19 vaccines.
—Kristen Jordan Shamus, Freep.com, 17 Sep. 2025
Kennedy has also questioned the safety and efficacy of mRNA vaccines, the technology that was used to develop the most effective COVID vaccines.
—Swapna Venugopal Ramaswamy, USA Today, 17 Sep. 2025
Note that abrasive brushes or sponges will leave small scratches on the surface, but, unlike with a nonstick pan, the scratches won’t damage the pan’s long-term efficacy.
—Emily Johnson, Bon Appetit Magazine, 15 Sep. 2025
See All Example Sentences for efficacy
Recent Examples of Synonyms for efficacy
Noun
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Première Vision has also extended its global footprint with events in New York, Montreal, Tokyo and Shenzhen, which Rousson said demonstrated the strength of PV and has not reduced the effectiveness of the original Paris fair.—
Rhonda Richford,
Footwear News,
22 Sep. 2025
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Bannon, for his part, slammed Kennedy's effectiveness as health secretary, calling his efforts to implement an anti-vaccine agenda unserious and amateurish.—
Beth Mole,
ArsTechnica,
22 Sep. 2025
Noun
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The company claims that the problem of the lack of waste heat in electric drive systems is elegantly solved by integrating a high-efficiency heat pump.—
Prabhat Ranjan Mishra,
Interesting Engineering,
20 Sep. 2025
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Such an overgrown standing army is undesirable, not on pacifist grounds, but purely from the standpoint of military efficiency.—
John Fischer,
Harpers Magazine,
19 Sep. 2025
Cite this Entry
“Efficacy.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/efficacy. Accessed 23 Sep. 2025.
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