efficaciousness

noun

Definition of efficaciousnessnext
as in efficacy
the power to produce a desired result the efficaciousness of exercise in improving physical as well as emotional well-being

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Example Sentences

Recent Examples of Synonyms for efficaciousness
  1. efficacy
  2. effectiveness
Noun
  • The protein building blocks can have anti-inflammatory and muscle-building properties – though studies and safety analyses of their benefits and efficacy as supplements or injections vary widely.
    — Cara Kelly, USA Today, 30 Aug. 2026
  • These second-generation antihistamines have similar efficacy, fewer undesirable side effects, and far less potential for abuse, according to the FDA.
    — Dr. Jill Grimes, CNN Money, 29 Aug. 2026
Definition of efficacy
Noun
  • Calcium and vitamin D are often supplemented together for bone health, but research shows mixed results on their effectiveness in improving bone mineral density or reducing fracture risk.
    — Jennifer Lefton, Verywell Health, 3 Sep. 2026
  • Milwaukee police officials have stood by the technology's effectiveness, despite months of criticism and two officers facing criminal charges for misuse of the system.
    — David Clarey, jsonline.com, 3 Sep. 2026
Definition of effectiveness
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.

Browse Nearby Words

efficacious
efficaciousness
efficacity
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Cite this Entry

“Efficaciousness.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/efficaciousness. Accessed 4 Sep. 2026.

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