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
Even more troubling, predatory supplement companies target youth with deceptive claims about the safety and efficacy of these products, claiming users will lose a rapid amount of weight or achieve a perfect body.
—
Jad Abdel Nour, Hartford Courant, 4 May 2026
Seigerman noticed Novo pounced on the opportunity and started to highlight the efficacy of oral semaglutide, the active ingredient in Novo's Wegovy, which delivered almost 17% weight loss in a separate trial.
—Angelica Peebles,elsa Ohlen,annika Kim Constantino, CNBC, 4 May 2026
The Atlanta-area congressman was the fifth House member to die during the 119th Congress, and the fourth Democrat, amid an ongoing debate over lawmakers’ age and efficacy.
—Joseph Konig, PEOPLE, 30 Apr. 2026
Compared to skin care’s need to wait for efficacy validation, color cosmetics offer immediate gratification, lower decision-making costs, and even the promise of going viral online.
—Denni Hu, Footwear News, 29 Apr. 2026
See All Example Sentences for efficacy
Jad Abdel Nour, Hartford Courant, 4 May 2026
Seigerman noticed Novo pounced on the opportunity and started to highlight the efficacy of oral semaglutide, the active ingredient in Novo's Wegovy, which delivered almost 17% weight loss in a separate trial.
—Angelica Peebles,elsa Ohlen,annika Kim Constantino, CNBC, 4 May 2026
The Atlanta-area congressman was the fifth House member to die during the 119th Congress, and the fourth Democrat, amid an ongoing debate over lawmakers’ age and efficacy.
—Joseph Konig, PEOPLE, 30 Apr. 2026
Compared to skin care’s need to wait for efficacy validation, color cosmetics offer immediate gratification, lower decision-making costs, and even the promise of going viral online.
—Denni Hu, Footwear News, 29 Apr. 2026
See All Example Sentences for efficacy
Recent Examples of Synonyms for efficacy
Noun
-
These processes monitor patient safety, clinical documentation, treatment outcomes and overall operational effectiveness, reinforcing a culture of accountability and consistency.—
Ascend Agency,
Sun Sentinel,
4 May 2026
-
The new data, which are released annually, follow a year of confusion and doubt in some quarters over the safety and effectiveness of vaccines.—
Lisa Schencker,
Chicago Tribune,
4 May 2026
Noun
-
For Hitler, the autobahn was a concrete expression of German efficiency and nationalism.—
Big Think,
Big Think,
1 May 2026
-
One of his long-term goals is to establish a dedicated marina, creating a centralized hub that enhances both efficiency and the customer experience.—
Daniel Fusch,
USA Today,
1 May 2026
Cite this Entry
“Efficacy.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/efficacy. Accessed 8 May. 2026.
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