placebo

noun pla·ce·bo \ plə-ˈsē-(ˌ)bō \

Updated on: 12 May 2018

Definition of placebo

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

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Recent Examples of placebo from the Web

Of 17 patients treated, 12 improved within a day compared to a placebo group, which saw no response.

— moises velasquez-manoff, WIRED, "Ketamine Stirs Up Hope—and Controversy—as a Depression Drug," 8 May 2018
But the drug, inteperdine, proved to be no better than placebo at improving cognition and function, a revelation that decimated Axovant’s share price and dashed Hung’s vision for the company.

— damian garde, STAT, "The stint that never happened? Biotech vet David Hung wipes Axovant from his work history," 10 Apr. 2018
But a large and growing body of research has found that homeopathy doesn’t work any better than a placebo.

— consumer reports, Washington Post, "‘Natural’ doctors face skepticism from practitioners of conventional medicine," 9 Apr. 2018
The researchers showed that around half of those trials showed antidepressants were more effective than a placebo.

— brigit katz, Smithsonian, "Major Study Finds Antidepressants Work, But May Have Limitations," 13 Mar. 2018
Drugs ranged from more than one third more effective than a placebo to more than twice as effective.

— katherine hignett, Newsweek, "Antidepressants Do Work, And Many More People Should Take Them: Major International Study," 22 Feb. 2018
The size of these fat cells in mice given the drug shrunk 30% after 10 days of treatment compared to those given a placebo.

— sy mukherjee, Fortune, "This Obesity Fighting Drug Could Melt Fat and Lower Cholesterol—Without Suppressing Your Appetite," 5 Jan. 2018
One hundred will get a placebo and the rest will get the treatment.

— ben brazil, latimes.com, "UC Irvine medical study gives hope to Orange County mom with ALS," 19 Apr. 2018
They were picked at random to receive either chemotherapy plus immunotherapy, or chemotherapy plus a placebo, with two-thirds receiving the combination that included immunotherapy.

— denise grady, BostonGlobe.com, "Lung cancer patients live longer with immune therapy," 17 Apr. 2018

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.

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.

Origin and Etymology of placebo

Latin, I shall please

NEW! Time Traveler

First Known Use: 1785

in the meaning defined at sense 1a

See Words from the same year

Other Pharmacology Terms

anodyne, cathartic, emetic, emollient, liniment, paregoric, poultice, purgative, soporific, spectrum

PLACEBO Defined for English Language Learners

placebo

noun

Definition of placebo for English Language Learners

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

Medical Dictionary

placebo

noun pla·ce·bo \ plə-ˈsē-(ˌ)bō \

medical Definition of placebo

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)

Learn More about placebo

Spanish Central: Translation of placebo Nglish: Translation of placebo for Spanish speakers Britannica English: Translation of placebo for Arabic speakers

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placebo

Definition of placebo

Recent Examples of placebo from the Web

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Origin and Etymology of placebo

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PLACEBO Defined for English Language Learners

placebo

Definition of placebo for English Language Learners

Medical Dictionary

placebo

medical Definition of placebo

Learn More about placebo

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Origin and Etymology of placebo

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PLACEBO Defined for English Language Learners

placebo

Definition of placebo for English Language Learners

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placebo

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