as in efficient
producing or capable of producing a desired result
taking a cookie break while studying is one of the most efficacious ways of rejuvenating the mind that I have ever discovered
Synonyms & Similar Words
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Antonyms & Near Antonyms
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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Antonyms & Near Antonyms
Example Sentences
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Recent Examples of efficacious
Bianca Salonga, Forbes.com, 1 Apr. 2025
Thorne is also rigorously tested and has worked with independent researchers from places like Mayo Clinic and the National Institutes of Health, to ensure its products are high-performance, safe, and efficacious.
—Vogue, 30 Mar. 2025
Despite Chief Justice Warren formally writing the opinion to apply exclusively to education, its attack on segregation has—paradoxically—been most efficacious beyond that original context.
—Justin Driver, The Atlantic, 15 Mar. 2025
Oh, that’s right, there’s a measles vaccines that is over 97% efficacious against the measles after two doses are administered, which people have been getting for years.
—Bruce Y. Lee, Forbes, 15 Mar. 2025
See All Example Sentences for efficacious
Adjective
These efficacious, natural ingredients include chamomile, California poppy, lemon verbena, linden, magnesium, rosemary and cardamom.
—Bianca Salonga, Forbes.com, 1 Apr. 2025
Thorne is also rigorously tested and has worked with independent researchers from places like Mayo Clinic and the National Institutes of Health, to ensure its products are high-performance, safe, and efficacious.
—Vogue, 30 Mar. 2025
Despite Chief Justice Warren formally writing the opinion to apply exclusively to education, its attack on segregation has—paradoxically—been most efficacious beyond that original context.
—Justin Driver, The Atlantic, 15 Mar. 2025
Oh, that’s right, there’s a measles vaccines that is over 97% efficacious against the measles after two doses are administered, which people have been getting for years.
—Bruce Y. Lee, Forbes, 15 Mar. 2025
See All Example Sentences for efficacious
Recent Examples of Synonyms for efficacious
Adjective
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An efficient storage system is a cost-effective storage system.—
Eric Herzog,
Forbes.com,
17 June 2025
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The time cap helped J.J. stay focused and efficient.—
Nasha Smith,
People.com,
16 June 2025
Noun
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Safety and efficacy vary highly between products; look for those that are independently tested and verified.—
Sarah Anzlovar,
Verywell Health,
9 June 2025
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This is a big problem in terms of the Presidents efficacy as well as well as his administration.—
Hollie Silverman,
MSNBC Newsweek,
9 June 2025
Adjective
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Second, sugarcane is more effective at sequestering carbon than corn.—
SJ Studio,
Sourcing Journal,
16 June 2025
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Podcasts are also an effective vehicle for incubating ideas that can be expanded in media such as TV, film and books, and for allowing promising talent to develop.—
Cynthia Littleton,
Variety,
16 June 2025
Adjective
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The oil-free version of its Vogue Verified counterpart, this one provides powerful antioxidant protection while limiting oil production and reducing breakouts through a potent blend of l-ascorbic acid, silymarin, ferulic acid, and salicylic acid.—
Jenny Berg,
Vogue,
13 June 2025
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This week, Drake teams up with Canadian rap newcomer Smiley, Kim Gordon has a potent pro-freedom message for Donald Trump, and Colombian hitmaker Feid surprise releases his seventh studio album.—
Rolling Stone,
Rolling Stone,
13 June 2025
Cite this Entry
“Efficacious.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/efficacious. Accessed 21 Jun. 2025.
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