from The American Heritage® Dictionary of the English Language, 4th Edition
- n. A substance containing no medication and prescribed or given to reinforce a patient's expectation to get well.
- n. An inactive substance or preparation used as a control in an experiment or test to determine the effectiveness of a medicinal drug.
- n. Something of no intrinsic remedial value that is used to appease or reassure another.
- n. Roman Catholic Church The service or office of vespers for the dead.
from the GNU version of the Collaborative International Dictionary of English
- n. The first antiphon of the vespers for the dead.
- n. A prescription with no pharmacological activity given to a patient to humor or satisfy the desire for medical treatment.
- n. 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.
from The Century Dictionary and Cyclopedia
- n. In the Roman Catholic Church, the vespers of the office for the dead.
- n. A medicine adapted rather to pacify than to benefit a patient.
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- n. an innocuous or inert medication; given as a pacifier or to the control group in experiments on the efficacy of a drug
- n. (Roman Catholic Church) vespers of the office for the dead
Middle English, from Late Latin placēbō, I shall please (the first word of the first antiphon of the service), first person sing. future tense of Latin placēre, to please; see plāk-1 in Indo-European roots.(American Heritage® Dictionary of the English Language, Fourth Edition)
From Latin placēbō ("I will please"), the first-person singular future active indicative of placeō ("I please"). (Wiktionary)