efficacy

noun ef·fi·ca·cy \ ˈe-fi-kə-sē \

Definition of efficacy

plural efficacies
:the power to produce an effect

Examples of efficacy in a Sentence

  1. In the planner's view, Rumsfeld had two goals: to demonstrate the efficacy of precision bombing and to "do the war on the cheap." —Seymour M. HershNew Yorker7 Apr. 2003
  2. Vaccines exist, but their efficacy against aerosolized plague is unknown. —Sharon Begley et al.Newsweek8 Oct. 2001
  3. efficacy does not have to be demonstrated before homeopathic products are marketed. —Alison Abbott et al.Nature26 Sept. 1996
  4. questioned the efficacy of the alarms in actually preventing auto theft

Recent Examples of efficacy from the Web

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'efficacy.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

Origin and Etymology of efficacy


EFFICACY Defined for English Language Learners

efficacy

noun

Definition of efficacy for English Language Learners

  • : the power to produce a desired result or effect



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