Efficacy

/ˈɛf.ɪ.kə.si/ · noun

Meaning

The ability to produce a desired effect under ideal testing conditions..

Definitions by Sense

1. The ability to produce a desired effect under ideal testing conditions.
2. A degree of ability to produce a desired effect; effectiveness.

Example Sentences

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.

[…]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.

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?

Toothbrush with improved efficacy

Synonyms for efficacy

Antonyms for efficacy

Related Words

Word Forms

• efficacies

Usage Notes

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