Dictionary

efficacy en · NOUN

Pronunciation

• /ˈef.ɪ.kə.si/ (Australia)
• /ˈɛf.ɪ.kə.si/ (Canada, General-American, Received-Pronunciation)
• [ˈef.ɪ.kə.sɪi] (Australia) cultivated
• (Southern-England) audio
• /ˈef.ə.kə.si/ (New-Zealand)

Etymology

From Old French efficace, from Late Latin efficācia (“efficacy”) (whence -acy), from efficāx (“efficacious”); see efficacious.

Meanings

1. (uncountable, usually) The ability to produce a desired effect under ideal testing conditions.
   • No method of verification known to science is applicable to the efficacy of prayer. […] If, then, the efficacy of prayer eludes the test of science, and if even uncertainty may rest upon the connection between an event asked in prayer, and the prayer that sought it, is there any evidence by which the efficacy of prayer may be tested and known? 1875, Rev. Professor Wallace, “Prayer in Relation to Natural Law”, in Science and Revelation, Belfast: William Mullan, →ISBN, page 43:
   • […]and this hath even made me ſuſpect the efficacy of reliques, to examine the bones, queſtion the habits and appurtenances of Saints, and even of Chriſt himſelf. 1642, Sir Thomas Browne, “Religio Medici [The Religion of a Doctor]”, in The Works Of the Learned Sr Thomas Brown, Kt., London: Tho. Basset et al., published 1686, page 15:
   • 2005, Flay et al. Standards of Evidence: Criteria for Efficacy, Effectiveness and Dissemination DOI: 10.1007/s11121-005-5553-y Efficacy refers to the beneficial effects of a program or policy under optimal conditions of delivery, whereas effectiveness refers to effects of a program or policy under more real-world conditions.
2. (uncountable, usually) A degree of ability to produce a desired effect; effectiveness.
   • Toothbrush with improved efficacy 1996, Moskovich, Patent application PCT/US1996/003658

Forms

Deriveds

bioefficacy · seroefficacy · nonefficacy · self-efficacy · inefficacy · coefficacy

Relateds

effector · effective · efficacious · effectuate · effectual · efficaciously · effect · effectivity · efficient · efficacity · efficiency · effectiveness

Synonyms

efficacity

Translations (45)

id khasiat (ability to produce effect) · id keampuhan (ability to produce effect) · ru эффекти́вность (ability to produce effect) · hu hatékonyság (ability to produce effect) · es eficacia (ability to produce effect) · ja 有効性 (ability to produce effect) · pl efektywność (ability to produce effect) · cmn 效驗 /效验 (ability to produce effect) · cmn 功效 (ability to produce effect) · sv effektivitet (ability to produce effect) · id kemanjuran (ability to produce effect) · pt eficácia (ability to produce effect) · de Wirksamkeit (ability to produce effect) · it efficacia (ability to produce effect) · nl doeltreffendheid (ability to produce effect) · fi tehokkuus (ability to produce effect) · de Wirkungsgrad (degree of ability to produce a desired effect) · ro eficacitate (ability to produce effect) · cs účinnost (ability to produce effect) · sk efektívnosť (ability to produce effect) · bg де́йственост (ability to produce effect) · id efikasi (ability to produce effect) · pl skuteczność (ability to produce effect) · ca eficàcia (ability to produce effect) · de Wirkungsfähigkeit (ability to produce effect) · grc δρᾶσις (ability to produce effect) · cmn 藥效 /药效 (ability to produce effect) · fr efficience (ability to produce effect) · fr efficacité (ability to produce effect) · la efficacitas (ability to produce effect) · ru де́йственность (ability to produce effect) · sl učinkovitost (ability to produce effect) · cmn 效能 (ability to produce effect) · de Wirkfähigkeit (ability to produce effect) · cmn 療效 /疗效 (ability to produce effect) · ia efficacia (ability to produce effect) · eo efikeco (ability to produce effect) · de Wirkungsvermögen (ability to produce effect) · az səmərə (ability to produce effect) · cs efektivnost (ability to produce effect) · cmn 效力 (ability to produce effect) · uk діє́вість (ability to produce effect) · uk ефекти́вність (ability to produce effect) · de Wirkvermögen (ability to produce effect) · az təsirlilik (ability to produce effect)