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placebo effect

[pluh-see-boh]
noun
  1. a reaction to a placebo manifested by a lessening of symptoms or the production of anticipated side effects.

Origin of placebo effect

First recorded in 1945–50
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for placebo effect

placebo effect

noun
  1. med a positive therapeutic effect claimed by a patient after receiving a placebo believed by him to be an active drugSee control group
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
placebo effect in Medicine

placebo effect

n.
  1. A beneficial effect in a patient following a particular treatment that arises from the patient's expectations concerning the treatment rather than from the treatment itself.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.