effectualness

noun

Definition of effectualnessnext
as in efficacy
the power to produce a desired result the effectualness of that new cancer treatment has yet to be proven

Synonyms & Similar Words

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Antonyms & Near Antonyms

Example Sentences

Recent Examples of Synonyms for effectualness
  1. efficacy
  2. effectiveness
Noun
  • Johnson, chairman of the subcommittee on investigations, had sought to open a parallel avenue of congressional investigation about Fauci's role in responding to the COVID-19 pandemic, including the safety and efficacy of the COVID-19 vaccines.
    — ABC News, ABC News, 14 Aug. 2026
  • However, Schneider is skeptical about the efficacy of flour as a pest repellent.
    — Ashley Chalmers, The Spruce, 14 Aug. 2026
Definition of efficacy
Noun
  • Under Kennedy, the FDA has set up extra hurdles for vaccine testing and blocked the publication of research into the effectiveness of COVID-19 shots.
    — Matthew Perrone, Chicago Tribune, 19 Aug. 2026
  • Under Kennedy, the FDA has also set up extra hurdles for vaccine testing and blocked the publication of research into the effectiveness of COVID-19 shots.
    — Ali Swenson, Los Angeles Times, 19 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

effectually
effectualness
effectuate
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Cite this Entry

“Effectualness.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/effectualness. Accessed 24 Aug. 2026.

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