How to Use efficacy in a Sentence

efficacy

noun
  • No crunch, greasy residue, or flakes here—just pure efficacy.
    — Catharine Malzahn, Glamour, 18 Mar. 2026
  • On the plus side, this improves efficacy and makes the serum last longer at the same time.
    — Glamour, 9 June 2022
  • This is a very new diet, so the research is out on its efficacy.
    — Karla Walsh, Woman's Day, 21 Dec. 2020
  • In at least a few cases, efficacy might even be beside the point.
    — J.c. Pan, The New Republic, 4 Aug. 2020
  • Also, the efficacy of the short-yardage running game is very much in doubt.
    — oregonlive, 11 May 2021
  • If there were, there’d be safety in numbers and a sense of efficacy.
    — Michael Shank, MSNBC Newsweek, 27 Oct. 2025
  • This deodorant earned top marks for its efficacy against sweat and odor.
    — Katrina Cossey, Parents, 22 Feb. 2024
  • Few skin saviors rival the best face masks in their efficacy.
    — Kiana Murden, Vogue, 12 Dec. 2025
  • Whether the same efficacy holds for children remains to be seen.
    — Wesley Kufel, The Conversation, 8 Dec. 2020
  • The dodgy data seem to have no bearing on the safety or efficacy of the drug.
    — The Economist, 28 Nov. 2019
  • Maybe the speed of the infection had something to do with the efficacy of the cure?
    — Kathryn Vanarendonk, Vulture, 11 Feb. 2026
  • They’re not allowed to look at efficacy.
    — Anjeanette Damon, ProPublica, 3 Apr. 2026
  • Ask what a treatment plan would look like, and how and when the two of you would evaluate its efficacy.
    — Terri Taylor, Wired, 29 Jan. 2021
  • As of now, the efficacy of this system has not been established.
    — New Atlas, 4 Oct. 2024
  • That’s in about the same range as typical efficacy for flu vaccines.
    — Brenda Goodman, CNN, 22 Nov. 2022
  • But the numbers depend in part on the efficacy of the vaccines that are ready for use soonest.
    — The Economist, 7 Oct. 2020
  • And while the vaccines are very protective, their efficacy wanes over time.
    — Josh Fischman, Scientific American, 13 June 2022
  • But the efficacy of that killswitch is unclear.
    — Thomas Brewster, Forbes.com, 25 June 2026
  • Since the drug is still being researched, that means all the data on its safety and efficacy isn’t in yet.
    — Syeda Khaula Saad, Verywell Health, 2 Apr. 2024
  • But all of that efficacy hasn't translated into the kinds of sales investors once hoped for.
    — Sy Mukherjee, Fortune, 25 Nov. 2019
  • This is also a great way to test the efficacy of your education!
    — Shyam Pradheep, Forbes, 17 July 2023
  • Now, doctors are sounding the alarm about the efficacy of some of the domestic drugs.
    — Alexandra Stevenson, New York Times, 25 Jan. 2025
  • If some customers were turned off by the sneaky charges, far more were turned on by Stiff Nights’ efficacy.
    — Matthew Hongoltz-Hetling, The New Republic, 23 June 2021
  • For that reason, the study failed to achieve its primary efficacy goal, which was a dose response.
    — Adam Feuerstein, STAT, 14 May 2026
  • If the safety and efficacy is there, the factory piece is being done.
    — Cnn Staff, CNN, 30 June 2020
  • Mukherjea said the timing of the doses could have an effect on efficacy.
    — Kellie Hwang, San Francisco Chronicle, 24 Sep. 2021
  • Pfizer is still likely to be the first out of the gate with interim results on efficacy.
    — Sarah Zhang, The Atlantic, 19 Oct. 2020
  • Searches were up at the start of the year as news emerged about the various vaccines and their levels of efficacy.
    — Washington Post, 29 Nov. 2021
  • The bride and groom are often able to take the reins, so coercion is lower and efficacy, higher.
    — Ananya Bhattacharya, Quartz India, 27 Nov. 2019
  • To date, there have not been any clinical trials testing the safety or efficacy of this trend.
    — Theara Coleman, TheWeek, 1 July 2026

Some of these examples are programmatically compiled from various online sources to illustrate current usage of the word 'efficacy.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

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