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

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 One third of patients in the trial will receive a placebo, while the remainder will receive a dose of the drug twice a day for either five or 10 days. Robert Hart, Forbes, 27 Sep. 2021 Two-thirds would receive the vaccine, and the rest would receive a placebo. The Washington Post, Arkansas Online, 27 July 2021 At the Northern California sites, two-thirds of the participants will receive the vaccine, while the other one-third will receive a placebo. Lila Seidman, Los Angeles Times, 10 June 2021 One child will receive a placebo for every two that get the active vaccine. Karen Weintraub, USA TODAY, 8 June 2021 In countries where people can now or will soon be able to be vaccinated, there is little incentive to enroll in a trial where they might be assigned to receive a placebo. Helen Branswell, STAT, 19 May 2021 Testing the drug’s effectiveness will require additional phases of tests and comparing the outcomes of patients treated with it with those who receive a placebo. New York Times, 6 Mar. 2021 Two-thirds of adolescent participants will get the vaccine, while the remainder will receive a placebo. Globe Staff, BostonGlobe.com, 3 Feb. 2021 Two-thirds of participants will be assigned to randomly receive two injections of vaccine administered 21 days apart, the remaining one-third will receive a placebo. Naomi Thomas, CNN, 28 Dec. 2020 See More

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.

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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Time Traveler for placebo

Time Traveler

The first known use of placebo was in 1785

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Dictionary Entries Near placebo

place bet

placebo

placebo effect

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Statistics for placebo

Last Updated

22 May 2022

Cite this Entry

“Placebo.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/placebo. Accessed 27 May. 2022.

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More Definitions for placebo

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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