efficacious

adjective

ˌe-fə-ˈkā-shəs How to pronounce efficacious (audio)
Definition of efficaciousnext
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

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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 Appealing to such a wide demographic is quite unique, and might speak to why the brand resonates: an intentional focus on effortless and efficacious beauty, which is something many women look for regardless of their age. —Clara Ludmir, Forbes.com, 14 Aug. 2025 French beauty lovers might already be familiar with Typology, one of the leading brands for simple, efficacious formulas. —Iman Balagam, Vogue, 11 July 2025 Rhode is dedicated to making products based in science and great formulation, simplifying many of the mysteries and complex narratives behind efficacious skincare. —Jason Pham, StyleCaster, 29 May 2025 On the other side are patients living with untreated diseases hoping that pharmaceutical companies will soon develop an efficacious treatment. —Wayne Winegarden, Forbes, 5 Mar. 2025 See All Example Sentences for efficacious
Recent Examples of Synonyms for efficacious
  1. efficient
  2. effective
  3. potent
Adjective
  • For a more comfortable, energy-efficient home, a number of upgrades are available too.
    — Miles Walls, Better Homes & Gardens, 8 Sep. 2025
  • Today, the most efficient way to earn that trust is to let AI amplify your story with an authentic touch.
    — Michael Ashley, Forbes.com, 8 Sep. 2025
Definition of efficient
Adjective
  • How To Clean Linoleum Floors With Vinegar Vinegar is effective at cleaning floors and disinfecting them, but for more cleaning power, add a few squirts of dish soap to the mix, which works well at removing grease and grime from floors.
    — Daley Quinn, Southern Living, 7 Sep. 2025
  • Alpine remains in a significant state of rebuild under Briatore, its effective boss.
    — Madeline Coleman, New York Times, 6 Sep. 2025
Definition of effective
Adjective
  • Other than making sure police are contacted, workers are instructed to take safety precautions and make sure that families understand the risk involved with the highly potent illicit drug.
    — Laura Bauer, Kansas City Star, 7 Sep. 2025
  • The most demanding users would probably like a more potent machine, like some of the larger options here, but the Blade 14 can largely serve as your mobile media-crunching PC when needed, and normal productivity tasks are mere snacks for it.
    — Matthew Buzzi, PC Magazine, 7 Sep. 2025
Definition of potent

Browse Nearby Words

effeteness
efficacious
efficaciousness
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Cite this Entry

“Efficacious.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/efficacious. Accessed 14 Sep. 2025.

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Nglish: Translation of efficacious for Spanish Speakers

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