as in effectiveness
the power to produce a desired result
questioned the efficacy of the alarms in actually preventing auto theft
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Recent Examples of efficacy
The efficacy of these lower-power cores remains to be seen, but Qualcomm notes that the chip is designed specifically for accessible, everyday computing.
—
John Burek, PC Magazine, 1 June 2026
These are the only doses that have been studied rigorously for safety and efficacy.
—Jody Dushay, STAT, 29 May 2026
For years, even as researchers challenged the long-term safety and efficacy of these expensive procedures, the federal government did little to stop potential abuse.
—Annie Waldman, ProPublica, 29 May 2026
Feigenbaum said that people using these drugs in spite of their limited efficacy and unknown risks are made up of two populations.
—T.m. Brown, CNN Money, 28 May 2026
See All Example Sentences for efficacy
John Burek, PC Magazine, 1 June 2026
These are the only doses that have been studied rigorously for safety and efficacy.
—Jody Dushay, STAT, 29 May 2026
For years, even as researchers challenged the long-term safety and efficacy of these expensive procedures, the federal government did little to stop potential abuse.
—Annie Waldman, ProPublica, 29 May 2026
Feigenbaum said that people using these drugs in spite of their limited efficacy and unknown risks are made up of two populations.
—T.m. Brown, CNN Money, 28 May 2026
See All Example Sentences for efficacy
Recent Examples of Synonyms for efficacy
Noun
-
Only 30% of the studies, or 23/77, even attempted to test for mask effectiveness.—
Ian Miller OutKick,
FOXNews.com,
1 June 2026
-
This in turn depends on their preferences for what is and is not covered based on many different factors, including products’ clinical- and cost-effectiveness, budgetary impact and other considerations.—
Joshua P. Cohen,
Forbes.com,
1 June 2026
Noun
-
Grutsch said the renovation builds in efficiency for each specific unit and purpose.—
Elliot Mann,
Twin Cities,
29 May 2026
-
One of its findings was that those countries that prioritized transitioning to clean energy alongside electrification and efficiency saved some $260 billion in fossil fuel import costs last year, with savings expected to grow substantially this year.—
Justin Worland,
Time,
29 May 2026
Cite this Entry
“Efficacy.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/efficacy. Accessed 7 Jun. 2026.
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