noun
( -s )
1. pläˈchā(ˌ)bō
[Middle English, from Latin, I shall please, 1st singular future indicative of placēre to please; from the initial word of the first antiphon, Ps 114:9 (Vulgate) — more at please ]
: the vespers for the dead in the Roman Catholic Church
2. pləˈsē(-
[Latin, I shall please]
a. : an inert medicament or preparation given for its psychological effect especially to satisfy the patient or to act as a control in an experimental series
b. : something tending to soothe or gratify
the placebo of illusions — Martin Gumpert