placebo

Etymology

From Middle English placebo, from Latin placēbō (“I will please”), the first-person singular future active indicative of placeō (“I please”).

noun

1. (medicine) A dummy medicine containing no active ingredients; an inert treatment.
   The acid test, I thought, was whether homeopathic remedies behave differently from placebos when submitted to clinical trials. 22 Feb 2010, Edzard Ernst, The Guardian
   The trials overall showed some but limited effectiveness, and in one of the largest and longest trials, the placebo performed better in treating spasticity, pain and bladder dysfunction, Dr. Bowling wrote. 2021-03-08, Jane E. Brody, “Medical Marijuana Is Not Regulated as Most Medicines Are”, in The New York Times
2. (Roman Catholicism) The vespers sung in the office for the dead.
   There the placebo, the office for the dead, was sung, and a vigil kept throughout the night. 2011, Thomas Penn, Winter King, Penguin, published 2012, page 349