efficacy

[ ef-i-kuh-see ]
/ ˈɛf ɪ kə si /
SEE SYNONYMS FOR efficacy ON THESAURUS.COM

noun, plural ef·fi·ca·cies.

capacity for producing a desired result or effect; effectiveness: a remedy of great efficacy.

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Origin of efficacy

1520–30; < Latin efficācia, equivalent to efficāc- (see efficacious) + -ia -y3

OTHER WORDS FROM efficacy

non·ef·fi·ca·cy, noun

Words nearby efficacy

effervescent, effervescent salt, effete, efficacious, efficacity, efficacy, efficiency, efficiency apartment, efficiency expert, efficient, efficient cause
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2020

Words related to efficacies

adequacy, effectiveness, competence, virtue, potency, vigor, use, strength, force, ability, power, efficaciousness, energy, influence, effect, weight, capability, performance, success, sufficiency

British Dictionary definitions for efficacies

efficacy
/ (ˈɛfɪkəsɪ) /

noun

the quality of being successful in producing an intended result; effectiveness
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