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
  • Ferulic acid, for its part, can help boost their stability and efficacy—which in sum made the formula more powerful than most antioxidant serums.
    — Deanna Pai, Vogue, 7 Aug. 2026
  • But researchers cautioned that the drug’s efficacy has not yet been proven.
    — The New Yorker, New Yorker, 7 Aug. 2026
Definition of efficacy
Noun
  • How closely matched the flu vaccine is to the dominant strain of the season is part of what accounts for the year-to-year changes in the shot’s effectiveness.
    — Elise Haulund, CNN Money, 14 Aug. 2026
  • Because supplements don't have to undergo FDA approval for safety or effectiveness before being sold, Wood also recommends looking for products independently tested by a reputable third party.
    — Dr. Onaola Adedeji, ABC News, 13 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 16 Aug. 2026.

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