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English definition of “efficacy”


noun [U]     /ˈef.ɪ.kə.si/ formal
an ability , especially of a medicine or a method of achieving something, to produce the intended result : They recently ran a series of tests to measure the efficacy of the drug . → Synonym effectivenessEfficient and effective
(Definition of efficacy noun from the Cambridge Advanced Learner's Dictionary & Thesaurus © Cambridge University Press)
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