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
  • As Kennedy has spent years questioning vaccine efficacy before becoming HHS Secretary, this messaging from an extremely influential health leader may have also contributed to vaccine hesitancy and declining vaccination rates.
    — Omer Awan, Forbes.com, 2 Aug. 2026
  • When the question is accumulated knowledge with years of safety and efficacy data, refined dosing, and better patient selection, sponsors are told that information doesn’t go the other way.
    — Kat Bryant Knudson, STAT, 31 July 2026
Definition of efficacy
Noun
  • The traditional flu shot ranges in effectiveness from 22% to 56%, according to the Mayo Clinic.
    — Berkeley Lovelace Jr, NBC news, 6 Aug. 2026
  • One of the reasons people are reluctant to get a flu shot is because of its sometimes weak effectiveness in protecting against symptoms.
    — Alice Park, Time, 6 Aug. 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 7 Aug. 2026.

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