🇬🇧 en fr 🇫🇷

efficacious adjective

  /ˌef.əˈkæɪ.ʃəs/ , /ˌɛf.əˈkeɪ.ʃəs/ , /ˌɛf.ɪˈkeɪ.ʃəs/
  • (formal) Effective; possessing efficacy. [from 1520s]
 efficace

efficacy noun

  /ˈɛf.ɪ.kə.si/
  • Degree of ability to produce a desired effect; effectiveness.
 efficacité, efficience

efficaciously

efficacement
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