Placebo

n.
  1. (R. C. Ch.) The first antiphon of the vespers for the dead.
  2. (Med.) A prescription with no pharmacological activity given to a patient to humor or satisfy the desire for medical treatment.
  3. (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.
    4. To sing placebo ,
    to agree with one in his opinion; to be complaisant to.