Placebo Definition

placeboes, placebos
A substance that has positive effects as a result of a patient's perception that it is beneficial rather than as a result of a causative ingredient.
American Heritage Medicine
A harmless, unmedicated preparation given as a medicine merely to humor a patient, or used as a control in testing the efficacy of another, medicated substance.
Webster's New World
The first antiphon of the vespers for the dead, beginning with the word placebo.
Webster's New World
Something said or done to win the favor of another.
Webster's New World
The definition of a placebo is a tablet, liquid, or other form of medication that actually contains no active ingredients, no actual medication or no therapeutic effect.
When you go to the doctor and claim you are sick but there is really nothing wrong with you and the doctor gives you a sugar pill that has no actual effect except appeasing your complaints, this sugar pill is an example of a placebo.
When a drug company is testing a new drug and gives one group a real pill and the other group gets a sugar pill, the sugar pill that he gives to the other group is an example of a placebo.

Other Word Forms of Placebo


placeboes, placebos

Origin of Placebo

  • Latin placēbō I shall please first person sing. future tense of Latin placēre to please plāk-1 in Indo-European roots Sense 3, from Late Latin placēbō I shall please, the first word of the first antiphon of the vespers service (taken from a phrase in the following psalm, placēbō Dominō in regiōne vīvōrum, “I shall please the Lord in the land of the living”)

    From American Heritage Dictionary of the English Language, 5th Edition

  • From Latin placÄ“bō (“I will please"), the first-person singular future active indicative of placeō (“I please").

    From Wiktionary


Find Similar Words

Find similar words to placebo using the buttons below.

Words Starting With

Words Ending With