YOUR VOCABULARY, ONE WORD AT A TIME

efficacy

Noun

IPA /ˈefɪkəsi/

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Meaning in plain English

The ability of a method or action to produce the result it is intended to achieve.

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Pronunciation

efficacy/ˈefɪkəsi/

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A method is used
It produces its intended result

Efficacy concerns how well a method achieves its purpose.

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Examples in context

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We compared the efficacy of two methods for removing the stain.
The study examined the efficacy of weekly vocabulary quizzes.

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We compared the ________ of two methods for removing the stain.

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efficacy — The ability of a method or action to produce the result it is intended to achieve.

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The ability of a method or action to produce the result it is intended to achieve.

Compare: We compared the efficacy of two methods for removing the stain.

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Word origin

From Latin efficacia, related to efficere, meaning to accomplish.

Did you know?

Evaluate the efficacy of something means assess how well it achieves its purpose.

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