placebo

noun

pla·​ce·​bo plə-ˈsē-(ˌ)bō How to pronounce placebo (audio)
plural placebos
1
a
: 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 The evidence for this startling finding comes by comparing side effects between patients allocated to the placebo shot versus those allocated to the real shot in the vaccine trials. TIME, 4 Apr. 2024 Because of volunteers’ hopes around a trial, even those who receive a placebo will often show more improvement than those who receive nothing. Brendan Borrell, New York Times, 21 Mar. 2024 The study found that compared to the placebo, people who took ginkgo biloba saw benefits such as better executive function, attention, mood, and non-verbal memory (meaning the ability to remember things that aren’t written or spoken). Discover Magazine, 12 Mar. 2024 Viking said Tuesday that a mid-stage trial showed that obese or overweight patients on the highest dose of its drug lost an average of about 14.7 percent of their body weight after injecting it once weekly for 13 weeks — 13 percent more weight loss than a placebo group. Daniel Gilbert, Washington Post, 27 Feb. 2024 The supplement users had half the number of errors on this test compared to those taking a placebo. Kristen Fischer, Health, 15 Mar. 2024 In studies, people with ADHD who took melatonin supplements had longer sleep times and better quality sleep compared to people who took a placebo. Discover Magazine, 12 Mar. 2024 In clinical trials, neither patients nor doctors are told who is on the placebo and who is on the experimental drug. Sarah Zhang, The Atlantic, 7 Mar. 2024 Disease-free survival for those with stage IV disease was about 68% in the vaccine-only group, and zero in the placebo group. Dr. Jade Cobern, ABC News, 20 Jan. 2024

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

Word History

Etymology

Latin, I shall please

First Known Use

1785, in the meaning defined at sense 1a

Time Traveler
The first known use of placebo was in 1785

Dictionary Entries Near placebo

Cite this Entry

“Placebo.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/placebo. Accessed 18 Apr. 2024.

Kids Definition

placebo

noun
pla·​ce·​bo plə-ˈsē-bō How to pronounce placebo (audio)
plural placebos
: a medicine that usually has no effect on a disease and is prescribed by a doctor for the mental relief it offers a patient
Etymology

from Latin placebo "I shall please"

Medical Definition

placebo

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

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