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efficacious

[ ef-i-key-shuhs ]
/ ˌɛf ɪˈkeɪ ʃəs /
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See synonyms for: efficacious / efficaciously / efficaciousness on Thesaurus.com

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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Origin of efficacious

First recorded in 1520–30; from Latin efficāci- (stem of efficax ) “effectual.” See efficient, -acious
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2021

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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

British Dictionary definitions for efficacious

efficacious
/ (ˌɛfɪˈkeɪʃəs) /

adjective

capable of or successful in producing an intended result; effective as a means, remedy, etc
efficaciously, adverbefficaciousness, noun
C16: from Latin efficāx powerful, efficient, from efficere to achieve; see effect
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
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