Definition of EFFICACIOUS

Examples of efficacious in a Sentence

taking a cookie break while studying is one of the most efficacious ways of rejuvenating the mind that I have ever discovered

Recent Examples of efficacious from the Web

There remain many open questions in the field—how, why, and in what circumstances cognitive training is efficacious—and so painting in such broad strokes potentially undermines this important, ongoing research area.

— beth mole, Ars Technica, "Study: Lumosity boosts brain function as much as normal video games—by 0%," 10 July 2017
If the pilot program proves efficacious, it would be expanded within Colorado’s 18,000-inmate population and perhaps across the nation.

— the denver post editorial board, The Denver Post, "Tablet computers could prove valuable in helping reform inmates," 15 May 2017
This kind of brain-science has already proven efficacious: a preliminary study of humans working with help from machinated neuron tapping showed a six-fold increase in efficiency.

— noah shachtman, WIRED, "Darpa Wants Brainy Machines to Replace Bored G.I.s," 16 Apr. 2009

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'efficacious.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

Origin and Etymology of efficacious

Latin efficac-, efficax, from efficere

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First Known Use: 1528

See Words from the same year

efficacious Synonyms

Synonym Discussion of efficacious

effective, effectual, efficient, efficacious mean producing or capable of producing a result. effective stresses the actual production of or the power to produce an effect. an effective rebuttal effectual suggests the accomplishment of a desired result especially as viewed after the fact. the measures to stop the pilfering proved effectual 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 efficacious suggests possession of a special quality or virtue that gives effective power. a detergent that is efficacious in removing grease

efficacious