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
Predictive analytics can assess trial feasibility based on population demographics, geographic factors and prior safety and efficacy data.
—
Avik Pal, Forbes.com, 6 May 2025
Public health experts were baffled by Mr. Kennedy’s decision to hunt for new treatments, rather than endorse shots that have decades of safety and efficacy data.
—Teddy Rosenbluth, New York Times, 2 May 2025
Kennedy has faced criticism over his past anti-vaccine advocacy, stirring doubts about the efficacy of the COVID-19 vaccine in particular.
—Julia Mueller, The Hill, 1 May 2025
There are safety measures in place to protect against the use of harmful mercury or lead in products, for example, but brands don’t have to prove the efficacy of cosmetic ingredients or submit drug requests with clinical studies to the FDA or any other regulatory body.
—Kara Nesvig, Allure, 24 Apr. 2025
See All Example Sentences for efficacy
Avik Pal, Forbes.com, 6 May 2025
Public health experts were baffled by Mr. Kennedy’s decision to hunt for new treatments, rather than endorse shots that have decades of safety and efficacy data.
—Teddy Rosenbluth, New York Times, 2 May 2025
Kennedy has faced criticism over his past anti-vaccine advocacy, stirring doubts about the efficacy of the COVID-19 vaccine in particular.
—Julia Mueller, The Hill, 1 May 2025
There are safety measures in place to protect against the use of harmful mercury or lead in products, for example, but brands don’t have to prove the efficacy of cosmetic ingredients or submit drug requests with clinical studies to the FDA or any other regulatory body.
—Kara Nesvig, Allure, 24 Apr. 2025
See All Example Sentences for efficacy
Recent Examples of Synonyms for efficacy
Noun
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Companies can achieve this level of efficiency and responsiveness within their supply chains.—
Viral Hirpara,
Forbes.com,
9 May 2025
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Its homes, which can be customized by combining various-sized modules, range from one to four bedrooms and are solar-powered, built to maximize thermal efficiency and indoor air quality.—
Sam Lubell,
Los Angeles Times,
9 May 2025
Cite this Entry
“Efficacy.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/efficacy. Accessed 12 May. 2025.
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