placebo

pla·ce·bo | \ plə-ˈsē-(ˌ)bō

plural placebos

Definition of placebo

1a : 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? Example Sentences Learn More about placebo

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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 In that study, which ended in 2009, HIV infections totaled 51 in the vaccine group and 74 in the placebo arm—an efficacy of 31%. — Jon Cohen, Science | AAAS, "Another HIV vaccine strategy fails in large-scale study," 2 Feb. 2020 Sometimes physicians also prescribe very low doses of active medications that function as placebos. — Sumathi Reddy, WSJ, "A Placebo for Pain Relief—Even When You Know It’s Not Real," 20 Jan. 2020 In the trial, conducted in about 12,000 participants over five years, more patients taking lorcaserin were diagnosed with cancer compared to patients taking a placebo, which was an inactive treatment. — Jacqueline Howard, CNN, "Weight loss drug Belviq tied to 'possible increased risk of cancer,' FDA says," 15 Jan. 2020 The approach was distinct from the one used in classical trials, in which participants are randomly selected to get either an intervention or a placebo, with neither the researchers nor the participants aware of which was administered. — Helen Branswell, STAT, "‘Against all odds’: The inside story of how scientists across three continents produced an Ebola vaccine," 7 Jan. 2020 The companies agreed, and sent him thousands of lactose placebos, pressed and stamped exactly like normal pills. — Alex W. Palmer, New York Times, "The China Connection: How One D.E.A. Agent Cracked a Global Fentanyl Ring," 17 Oct. 2019 Tolperisone relieved pain as rated by patients and produced the same amount of drowsiness as the placebo, the study found. — San Diego Union-Tribune, "Neurana’s non-opioid back pain drug passes midstage human testing," 24 Sep. 2019 In place of a placebo control, the rings were randomly assigned to either immediate vaccination, or vaccination after a 21-day delay. — Helen Branswell, STAT, "‘Against all odds’: The inside story of how scientists across three continents produced an Ebola vaccine," 7 Jan. 2020 This is compared to roughly 12% and 28%, respectively, from the placebo. — Michael Nedelman, CNN, "FDA approves new drug for migraine sufferers," 23 Dec. 2019

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.