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placebo

noun pla·ce·bo \ plə-ˈsē-(ˌ)bō \
|Updated on: 7 Jul 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

See placebo defined for English-language learners

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Recent Examples of placebo from the Web

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

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

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

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