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placebo

[pluh-see-boh for 1; plah-chey-boh for 2]
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noun, plural pla·ce·bos, pla·ce·boes.
  1. Medicine/Medical, Pharmacology.
    1. a substance having no pharmacological effect but given merely to satisfy a patient who supposes it to be a medicine.
    2. a substance having no pharmacological effect but administered as a control in testing experimentally or clinically the efficacy of a biologically active preparation.
  2. Roman Catholic Church. the vespers of the office for the dead: so called from the initial word of the first antiphon, taken from Psalm 114:9 of the Vulgate.

Origin of placebo

1175–1225 for def 2; 1775–85 for def 1; Middle English < Latin placēbō I shall be pleasing, acceptable
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

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British Dictionary definitions for placebo

placebo

noun plural -bos or -boes
  1. med an inactive substance or other sham form of therapy administered to a patient usually to compare its effects with those of a real drug or treatment, but sometimes for the psychological benefit to the patient through his believing he is receiving treatmentSee also control group, placebo effect
  2. something said or done to please or humour another
  3. RC Church a traditional name for the vespers of the office for the dead

Word Origin

C13 (in the ecclesiastical sense): from Latin Placebo Domino I shall please the Lord (from the opening of the office for the dead); C19 (in the medical sense)
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Word Origin and History for placebo

n.

early 13c., name given to the rite of Vespers of the Office of the Dead, so called from the opening of the first antiphon, "I will please the Lord in the land of the living" (Psalm cxiv:9), from Latin placebo "I shall please," future indicative of placere "to please" (see please). Medical sense is first recorded 1785, "a medicine given more to please than to benefit the patient." Placebo effect attested from 1950.

Online Etymology Dictionary, © 2010 Douglas Harper

placebo in Medicine

placebo

([object Object])
n. pl. pla•ce•bos
  1. A substance containing no medication and prescribed or given to reinforce a patient's expectation to get well.
  2. An inactive substance or preparation used as a control in an experiment or test to determine the effectiveness of a medicinal drug.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.

placebo in Science

placebo

[plə-sēbō]
  1. A substance containing no medication and prescribed to reinforce a patient's expectation of getting well or used as a control in a clinical research trial to determine the effectiveness of a potential new drug.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

placebo in Culture

placebo

[(pluh-see-boh)]

A substance containing no active drug, administered to a patient participating in a medical experiment as a control.

Note

Those receiving a placebo often get better, a phenomenon known as the placebo effect.
The New Dictionary of Cultural Literacy, Third Edition Copyright © 2005 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
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