TRANQUILIZE

[tran.quil.ize] also tran.quil.lize vb -ized also -lized ; -iz.ing also -liz.ing vt (1623): to make tranquil or calm: pacify; esp: to relieve of mental tension and anxiety by means of drugs ~ vi 1: to become tranquil: relax 1

2: to make one tranquil