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efficacious
[ ef-i-key-shuhs ]
/ ˌɛf ɪˈkeɪ ʃəs /
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This shows grade level based on the word's complexity.
adjective
capable of having the desired result or effect; effective as a means, measure, remedy, etc.: The medicine is efficacious in stopping a cough.
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Which of the following words describes “sky blue”?
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Origin of efficacious
OTHER WORDS FROM efficacious
Words nearby efficacious
effervescence, effervescent, effervescent salt, effete, Effexor, efficacious, efficacity, efficacy, efficiency, efficiency apartment, efficiency expert
Dictionary.com Unabridged
Based on the Random House Unabridged Dictionary, © Random House, Inc. 2021
WHEN TO USE
What are other ways to say efficacious?
The adjective efficacious describes things that are capable of having the desired result or effect. But efficacious isn’t quite the same as effectual, effective, or efficient! Find out why on Thesaurus.com.
How to use efficacious in a sentence
British Dictionary definitions for efficacious
efficacious
/ (ˌɛfɪˈkeɪʃəs) /
adjective
capable of or successful in producing an intended result; effective as a means, remedy, etc
Derived forms of efficacious
efficaciously, adverbefficaciousness, nounWord Origin for efficacious
C16: from Latin efficāx powerful, efficient, from efficere to achieve; see effect
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition
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