from The American Heritage® Dictionary of the English Language, 5th Edition.

  • noun 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.
  • noun An inactive substance or preparation used as a control in an experiment or test to determine the effectiveness of a medicinal drug.
  • noun Something of no intrinsic remedial value that is used to appease or reassure another.
  • noun Roman Catholic Church The service or office of vespers for the dead.

from The Century Dictionary.

  • noun In the Roman Catholic Church, the vespers of the office for the dead.
  • noun A medicine adapted rather to pacify than to benefit a patient.

from the GNU version of the Collaborative International Dictionary of English.

  • noun (R. C. Ch.) The first antiphon of the vespers for the dead.
  • noun (Med.) A prescription with no pharmacological activity given to a patient to humor or satisfy the desire for medical treatment.
  • noun (Med.) a dose of a compound having no pharmacological activity given to a subject in a medical experiment as part of a control experiment in a test of the effectiveness of another, active pharmacological agent.
  • noun to agree with one in his opinion; to be complaisant to.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

  • noun an innocuous or inert medication; given as a pacifier or to the control group in experiments on the efficacy of a drug
  • noun (Roman Catholic Church) vespers of the office for the dead


from The American Heritage® Dictionary of the English Language, 4th Edition

[Latin placēbō, I shall please, first person sing. future tense of Latin placēre, to please; see plāk- 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 Wiktionary, Creative Commons Attribution/Share-Alike License

From Latin placēbō ("I will please"), the first-person singular future active indicative of placeō ("I please").


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  •  The term placebo: an inert medication or bogus treatment that is intended to control for expectancy effects.

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  • The pharmaceutical industry including some prominent researchers and supposed regulators continue to insist that testing new drugs against a placebo is the only way to get scientifically valid and meaningful results even though administration of placebos means some subjects get no treatment at all.

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  • PHILIPS: Well, I think there is what we call a placebo effect.

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  • But Scriba said doctors aren't obliged to actually use the word 'placebo.'

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  • And although doctors don't have to use the word "placebo," they should tell patients they are getting an unusual treatment.

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  • But Scriba said doctors aren't obliged to actually use the word 'placebo.'

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  • Biases are present in placebo-controlled trials of both homoeopathy and conventional medicine.

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  • If yesterday was about admitting and addressing the illness, today and tomorrow will hopefully be about prescribing a direction for recovery [not a short-term placebo].

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  • In clinical trials, moodiness was more common among users of Ortho Tri Cyclen than in placebo users, but overall occurred in less than 10% of users.

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  • In the first instance, the word placebo comes to mind.

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