Find Synonyms

efficacy Synonyms

Another word for efficacy

Choosing another word for efficacy that fits your sentence is easier when synonyms and similar words are paired with an exact noun definition and ranked by match strength.
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• noun (Context 1)

The ability or capacity to produce a desired or intended result, especially under controlled or ideal conditions.

Usage Example

"Researchers conducted a three-year clinical trial to evaluate the long-term effectiveness of the new vaccine."

Strongest
effectiveness
Strong
potency
success
power
productiveness
Weak
utility

Opposites of efficacy

The opposite of efficacy shifts depending on context. Common opposites include:

inefficacy
ineffectiveness
futility
impotence
uselessness
inadequacy
See all opposites of efficacy

• Nearby Words

effervesce
effervescence
effervescent
efficacy
efficiency
efficient
efficiently

Cite this Entry

Wordmom. (2026). Synonyms for Efficacy. In Wordmom Thesaurus. Retrieved Nov 5, 2026, from https://wordmom.com/synonyms/efficacy
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