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
Oncologists want to know if that broad activity leads to broad efficacy.
—
Lisa Jarvis, Twin Cities, 7 June 2026
According to the Centers for Disease Control and Prevention (CDC), some studies report that certain essential oils, like peppermint oil and rosemary oil, have some efficacy for tick control.
—Dan Simms, USA Today, 4 June 2026
Oncologists want to know if that broad activity leads to broad efficacy.
—Lisa Jarvis, Mercury News, 4 June 2026
Safety and efficacy have not been evaluated in pregnant women, pediatric users, people with active cancer or cancer in remission, or users with uncontrolled hypertension, hypotension, bradycardia or tachycardia.
—Samantha Agate, Sacbee.com, 3 June 2026
See All Example Sentences for efficacy
Lisa Jarvis, Twin Cities, 7 June 2026
According to the Centers for Disease Control and Prevention (CDC), some studies report that certain essential oils, like peppermint oil and rosemary oil, have some efficacy for tick control.
—Dan Simms, USA Today, 4 June 2026
Oncologists want to know if that broad activity leads to broad efficacy.
—Lisa Jarvis, Mercury News, 4 June 2026
Safety and efficacy have not been evaluated in pregnant women, pediatric users, people with active cancer or cancer in remission, or users with uncontrolled hypertension, hypotension, bradycardia or tachycardia.
—Samantha Agate, Sacbee.com, 3 June 2026
See All Example Sentences for efficacy
Recent Examples of Synonyms for efficacy
Noun
-
This emphasis on user-friendly effectiveness is immediately apparent in CyberFOX’s simple setup approach.—
Wyles Daniel,
USA Today,
8 June 2026
-
Ervin recommends placing these about eight feet apart for maximum effectiveness.—
Sarah Lyon,
The Spruce,
8 June 2026
Noun
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For many carriers, adapting existing infrastructure without disrupting efficiency models remains one of the largest barriers to change.—
Omar Leigh,
Forbes.com,
12 June 2026
-
Since taking the reins at the RSN in October 2024, Wisnia has done his bit to boost in-game deliveries—the Red Sox closed out last season up 46% in average household ratings—while spearheading an efficiency review that gave way to the relaunch of NESN’s direct-to-consumer service.—
Anthony Crupi,
Sportico.com,
12 June 2026
Cite this Entry
“Efficacy.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/efficacy. Accessed 13 Jun. 2026.
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