Synonym Chooser

How does the adjective efficacious contrast with its synonyms?

Some common synonyms of efficacious are effective, effectual, and efficient. While all these words mean "producing or capable of producing a result," efficacious suggests possession of a special quality or virtue that gives effective power.

a detergent that is efficacious in removing grease

When is effective a more appropriate choice than efficacious?

In some situations, the words effective and efficacious are roughly equivalent. However, effective stresses the actual production of or the power to produce an effect.

an effective rebuttal

When would effectual be a good substitute for efficacious?

Although the words effectual and efficacious have much in common, effectual suggests the accomplishment of a desired result especially as viewed after the fact.

the measures to stop the pilfering proved effectual

When can efficient be used instead of efficacious?

While the synonyms efficient and efficacious are close in meaning, efficient suggests an acting or a potential for action or use in such a way as to avoid loss or waste of energy in effecting, producing, or functioning.

an efficient small car

Example Sentences

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.
Recent Examples of efficacious Studies have shown navel administration of medication is efficacious and that navel oiling can help with digestion, as well as potentially relieve gynecological discomfort. Margaux Anbouba, Vogue, 18 Dec. 2024 Research suggests that the use of antiretroviral drugs and advances in managing HIV infections have helped make solid organ transplants in people with HIV safer and more efficacious. Jacqueline Howard, CNN, 27 Nov. 2024 The muses may hold a pen in one hand and a smoke, or steaming mug, in the other—herbal remedies continue to be efficacious for writer’s block. Alison Habens, JSTOR Daily, 31 Oct. 2024 Truth be told, Hinds was skeptical that an efficacious facial could be done in a half-hour. Jennifer Weil, WWD, 18 Oct. 2024 See All Example Sentences for efficacious
Recent Examples of Synonyms for efficacious
Adjective
  • This uptick in market interest coincided with more efficient manufacturing practices and a growing interest in fashion after the boom of economic growth post-World War II.
    Brett F. Braley-Palko, Forbes, 1 Mar. 2025
  • It's called Ocelot – because it's got 'cat qubits' inside – and it's said to be significantly more efficient at error correction.
    New Atlas, New Atlas, 28 Feb. 2025
Adjective
  • Expert instructors will teach you how to get started, practical uses, tips for effective prompt-writing, and mistakes to avoid.
    Ryan Johnston, CNBC, 28 Feb. 2025
  • One dose is 93% effective, and two doses are 97% effective.
    Mary Kekatos, ABC News, 28 Feb. 2025
Adjective
  • Watson joined the Chiefs in 2022, and his speed helped the team field one of the most potent offenses in the league.
    Nate Taylor, The Athletic, 11 Mar. 2025
  • Kentucky also boasts a potent offense led by several dangerous shooters, even after leading scorer Jaxson Robinson's unfortunate season-ending injury.
    William Lambers, Newsweek, 10 Mar. 2025

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Cite this Entry

“Efficacious.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/efficacious. Accessed 13 Mar. 2025.

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