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efficacy

[ef-i-kuh-see] / ˈɛf ɪ kə si /


Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

The company reported positive results for two studies of its elecoglipron experimental drug, which showed competitive efficacy with a standard safety profile, the analysts say.

From The Wall Street Journal • Jun. 9, 2026

The analysts at Citi also highlighted what they said were real-world signals of waning efficacy in Wegovy pill as roughly a quarter to a third of patients are no longer losing weight.

From MarketWatch • Jun. 8, 2026

Leaving efficacy to doctors would help Americans lead longer, healthier lives.

From The Wall Street Journal • Jun. 1, 2026

They add: "Assessing long-term efficacy is critical since those who work night shifts for many years would need to consistently consume melatonin supplements over that time frame to maximize the potential cancer prevention benefits."

From Science Daily • May 30, 2026

Three were scientists checking the efficacy of sprays; 8 worked in greenhouses; 5 were farm workers.

From "Silent Spring" by Rachel Carson




Vocabulary lists containing efficacy


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