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
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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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The company discontinued the 5.7-liter engine amid tightening fuel economy regulations and a companywide push toward electric vehicles and more efficient engines last year under ex-Stellantis CEO Carlos Tavares.—
Michael Wayland,
CNBC,
5 June 2025
-
These coverage losses were avoidable with better, more efficient communication.—
Lisa Fitzpatrick,
Forbes.com,
5 June 2025
Noun
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Moreover, researchers have conducted thorough evaluations of the vaccines in pregnant women, confirming their safety and efficacy in this demographic.—
Dave Wessner,
Forbes.com,
29 May 2025
-
Realistically, this Phase I trial – which tests for safety and efficacy, as well as dose parameters – should be completed by some time next year, and if successful will move to the next stage, involving a larger population.—
Bronwyn Thompson,
New Atlas,
26 May 2025
Adjective
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Are Mineral Sunscreens Better Than Chemical Sunscreens? Mineral and chemical sunscreens are both effective, but contain different active ingredients.6 Mineral sunscreens (or physical sunscreens) primarily contain titanium dioxide, zinc oxide, or both.—
Sherri Gordon,
Health,
4 June 2025
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The ignition method was strikingly consistent: a crude yet effective time-delay mechanism, fashioned from everyday items like cigarettes, matches, and pieces of lined yellow notebook paper.—
JP Mangalindan,
Time,
4 June 2025
Adjective
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Worthy Park Estate 109 Rum From the heart of Jamaica, Worthy Park's 109 is a potent invitation to pure, unadulterated rum flavor.—
Hudson Lindenberger,
Forbes.com,
2 June 2025
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His potent bat has carried the lineup in two of his first three seasons in town, the other being slowed by his first foot injury.—
Dan Hayes,
New York Times,
2 June 2025
Cite this Entry
“Efficacious.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/efficacious. Accessed 15 Jun. 2025.
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