Word.ws English Dictionary

efficacies

efficacies is the plural of efficacy.

Meaning of efficacy

Noun

efficacy (usually uncountable, plural efficacies)

  1. (usually) The ability to produce a desired effect under ideal testing 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.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
  2. (usually) A degree of ability to produce a desired effect; effectiveness.
    • Toothbrush with improved efficacy1996, Moskovich, Patent application PCT/US1996/003658

Questions about efficacies

What is efficacies the plural of?
Efficacies is the plural of efficacy.

Words near efficacies in the dictionary

  1. effet
  2. effete
  3. effetely
  4. effeteness
  5. effets
  6. efficacies
  7. efficacious
  8. efficaciously
  9. efficaciousness
  10. efficacities
  11. efficacity

Source and license

Adapted from Wiktionary: efficacies (page history and authors); efficacy (page history and authors). Text available under the Creative Commons Attribution-ShareAlike 4.0 license. Word.ws reformatted the entry and added links. Wiktionary data of 2026-09-02.

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