efficacy

Meaning

1. (uncountable, usually) The ability to produce a desired effect under ideal testing conditions.
2. (uncountable, usually) A degree of ability to produce a desired effect; effectiveness.

Synonyms

effectiveness

effect

efficiency

potency

efficaciousness

effectivity

virtue

success

effective

validity

effectuality

fruitfulness

result

effectualness

benefit

productiveness

yield

utility factor

practical effect

prevalency

active force

remain valid

achievement

efficacity

cogency

competency

force

impression

merit

meritorious

operation

output

performance

potentiality

power

prevalence

productivity

usefulness

work

Translations

efficacité

eficacia

Wirksamkeit

efficacia

Wirkung

eficácia

eficàcia

doeltreffendheid

rendement

Erfolg

Effektivität

Wirkungskraft

Effizienz

Effekt

Pronounced as (IPA)

/ˈɛf.ɪ.kə.si/

Etymology

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