EFFICACIOUS


Meaning of EFFICACIOUS in English

/ ˌefɪˈkeɪʃəs; NAmE / adjective

( formal ) (of things, not of people) producing the result that was wanted or intended

SYN effective :

They hope the new drug will prove especially efficacious in the relief of pain.

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WORD ORIGIN

early 16th cent.: from Latin efficax , efficac- (from efficere accomplish, from ex- out, thoroughly + facere do, make) + -ious .

Oxford Advanced Learner's English Dictionary.      Оксфордский английский словарь для изучающик язык на продвинутом уровне.