efficacy
noun | /efficacy/
Essential WordsHARD
the ability to produce a desired result or effect
efficacy
noun | /efficacy/
Essential WordsHARDthe ability to produce a desired result or effect
Learning Progress
Synonyms
effectivenesspotencysuccessusefulness
Antonyms
ineffectivenessimpotencefailure
Examples
"The new policy's efficacy will be assessed over the next year."
"Clinical trials measure the efficacy of the drug."
Etymology
from Latin efficacia “power to produce effect”
Source: Essential WordsAdded: 11/13/2025
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