What is Efficacy?
The definition of efficacy is to perform a task to a satisfactory degree. It’s the ability to accomplish something and produce a desired result.
In the technical sense, it also refers to how well a drug, treatment, or product works.
- efficacy is the power to produce a desired effect or result
- it is also how well a product/drug works
- common synonyms are effectiveness and efficiency
Efficacy is the perfect word to describe if something (or someone) produces a result you want. When discussing a product’s efficacy, you’re talking about its effectiveness and ability to do what it is supposed to.
The word itself comes from the Latin efficãcia, from 1520-30, and it was considered the equivalent of efficãc (effective).
Because of its positive/beneficial meaning, it can be a great way to illustrate how efficient a product is, for example: “that moisturizer has an 80% efficacy in fighting my seasonal dry skin!”« Back to Glossary Index