EFFICACIOUSNESS Synonyms: 22 Similar and Opposite Words

efficaciousness

noun

Definition of efficaciousness

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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Recent Examples of Synonyms for efficaciousness

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

Implement a digital visual-management platform across six facilities to standardize workflows and improve infection prevention, care coordination, workforce effectiveness, quality, and patient safety.

— Arkansas Democrat-Gazette, Arkansas Online, 27 Aug. 2026
Apart from the penalty, Meta agreed as part of the settlement to algorithmic changes that could dampen engagement and the effectiveness of its advertising, dampening investor sentiment toward the resolution of the case.

— Tobias Burns, CNBC, 26 Aug. 2026

Definition of effectiveness

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efficacious

efficaciousness

efficacity

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“Efficaciousness.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/efficaciousness. Accessed 1 Sep. 2026.

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Synonyms of efficaciousness

noun

Example Sentences

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