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
Now, doctors are sounding the alarm about the efficacy of some of the domestic drugs.
—
Alexandra Stevenson, New York Times, 25 Jan. 2025
Some of the senators tried to show him data, referencing the deep scientific literature supporting the safety and efficacy of vaccines, including the Measles, Mumps, and Rubella Vaccine (MMR) and the HPV vaccine.
—Ars Technica, 31 Jan. 2025
Not to mention, research suggests there is no safety or efficacy benefit to getting the drug prescribed by a doctor in person (with testing, like an ultrasound) versus receiving it in the mail without any prior testing.
—Korin Miller, SELF, 29 Jan. 2025
This effectively meant the creatine doubled the efficacy of the psychotherapy, with 12 participants in the supplement group achieving full remission at the end of the eight weeks compared to just five in the placebo group.
—Rich Haridy, New Atlas, 29 Jan. 2025
See all Example Sentences for efficacy 
Alexandra Stevenson, New York Times, 25 Jan. 2025
Some of the senators tried to show him data, referencing the deep scientific literature supporting the safety and efficacy of vaccines, including the Measles, Mumps, and Rubella Vaccine (MMR) and the HPV vaccine.
—Ars Technica, 31 Jan. 2025
Not to mention, research suggests there is no safety or efficacy benefit to getting the drug prescribed by a doctor in person (with testing, like an ultrasound) versus receiving it in the mail without any prior testing.
—Korin Miller, SELF, 29 Jan. 2025
This effectively meant the creatine doubled the efficacy of the psychotherapy, with 12 participants in the supplement group achieving full remission at the end of the eight weeks compared to just five in the placebo group.
—Rich Haridy, New Atlas, 29 Jan. 2025
See all Example Sentences for efficacy
Thesaurus Entries Near efficacy
Cite this Entry
“Efficacy.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/efficacy. Accessed 22 Feb. 2025.
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