placebo effect

American  

[pluh-see-boh] / pləˈsi boʊ /

noun

1. a reaction to a placebo manifested by a lessening of symptoms or the production of anticipated side effects.

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placebo effect British  

noun

1. med a positive therapeutic effect claimed by a patient after receiving a placebo believed by him to be an active drug See control group

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Etymology

Origin of placebo effect

First recorded in 1945–50

Example Sentences

See Examples For:

placebo effect

The company is leaning toward a trial that compares patients receiving the therapy against a control group receiving standard treatments and a “sham” procedure to rule out any placebo effect.

From Barron's ● Jun. 17, 2026

The other half received a sham treatment designed to control for the placebo effect.

From Science Daily ● May 22, 2026

Only 15% of people with major depression experienced a substantial benefit from taking antidepressants beyond the placebo effect, according to a 2022 study.

From The Wall Street Journal ● May 4, 2026

GP Ben Davis also warns that TRT can have a placebo effect, leaving patients sometimes taking and paying for medication privately, that they do not need.

From BBC ● Feb. 14, 2026

It must have been a placebo effect, but it was a great placebo effect.

From "It’s Kind of a Funny Story" by Ned Vizzini