Definition of efficacious
: having the power to produce a desired effect an efficacious remedy
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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
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.
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
First Known Use: 1528
Synonym Discussion of efficacious
EFFICACIOUS Defined for English Language Learners
Definition of efficacious for English Language Learners
: having the power to produce a desired result or effect
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