placebo

noun
pla·​ce·​bo | \ plə-ˈsē-(ˌ)bō How to pronounce placebo (audio) \
plural placebos

Definition of placebo

1a : a usually pharmacologically inert preparation prescribed more for the mental relief of the patient than for its actual effect on a disorder
b : an inert or innocuous substance used especially in controlled experiments testing the efficacy of another substance (such as a drug)
2 : something tending to soothe

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Did You Know?

Doctors doing research on new treatments for disease often give one group a placebo while a second group takes the new medication. Since those in the placebo group usually believe they're getting the real thing, their own hopeful attitude may bring about improvement in their condition. Thus, for the real drug to be considered effective, it must produce even better results than the placebo. Placebos have another use as well. A doctor who suspects that a patient's physical symptoms are psychologically produced may prescribe a placebo in the hope that mentally produced symptoms can also be mentally cured.

Examples of placebo in a Sentence

Recent Examples on the Web The researchers recorded 18 cases of symptomatic coronavirus infection in the placebo group, and none among the children who received the vaccine. New York Times, "The Pfizer-BioNTech Vaccine Is Said to Be Powerfully Protective in Adolescents," 31 Mar. 2021 Nine percent had to discontinue the treatment because of side-effects, compared with 3% in the placebo group. Anna Kuchment, Dallas News, "New drug doubles disease-free survival in esophageal cancer," 31 Mar. 2021 During the study, which began earlier this year, 18 teens developed COVID-19, all of them in the placebo group. Alice Park, Time, "Pfizer-BioNTech's COVID-19 Vaccine Works for Teens, According to a New Study," 31 Mar. 2021 Among patients receiving lenzilumab, the death rate was 9.6%, compared with 13.9% in the placebo group. Joseph Walker, WSJ, "Pair of Covid-19 Drugs Performed Well in Studies, Makers Say," 29 Mar. 2021 Eight people in the placebo group developed severe disease, but none of the vaccine recipients who became ill progressed beyond moderate symptoms. Jon Cohen, Science | AAAS, "AstraZeneca lowers efficacy claim for COVID-19 vaccine, a bit, after board's rebuke," 25 Mar. 2021 At the end of the three months, those who consumed any amount of vinegar had a lower body weight, a smaller body mass index, less visceral fat, a smaller waist measurement and lower triglyceride levels than the placebo group that drank no vinegar. Sandee Lamotte, CNN, "Apple cider vinegar and weight loss -- what the experts say," 24 Mar. 2021 Such studies include two rounds, and in the second one the placebo group receives the vaccine, and vice versa. Jared Whitlock, Wired, "The US Has 3 Covid Vaccines—Testing New Ones Is Complicated," 11 Mar. 2021 There were only four hospitalizations and no deaths among the treatment group, while there were 15 hospitalizations and four deaths among the placebo group. David Hogberg, Washington Examiner, "Eli Lilly antibody therapy effective at cutting COVID-19 hospitalizations and deaths," 10 Mar. 2021

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'placebo.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of placebo

1785, in the meaning defined at sense 1a

History and Etymology for placebo

Latin, I shall please

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Learn More about placebo

Time Traveler for placebo

Time Traveler

The first known use of placebo was in 1785

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Statistics for placebo

Last Updated

4 Apr 2021

Cite this Entry

“Placebo.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/placebo. Accessed 10 Apr. 2021.

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More Definitions for placebo

placebo

noun

English Language Learners Definition of placebo

medical : a pill or substance that is given to a patient like a drug but that has no physical effect on the patient

placebo

noun
pla·​ce·​bo | \ plə-ˈsē-(ˌ)bō How to pronounce placebo (audio) \
plural placebos

Medical Definition of placebo

1 : a usually pharmacologically inert preparation prescribed more for the mental relief of the patient than for its actual effect on a disorder
2 : an inert or innocuous substance used especially in controlled experiments testing the efficacy of another substance (as a drug)

More from Merriam-Webster on placebo

Nglish: Translation of placebo for Spanish Speakers

Britannica English: Translation of placebo for Arabic Speakers

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