'Tranquilize' definitions:

Definition of 'tranquilize'

(from WordNet)
verb
Make calm or still; "quiet the dragons of worry and fear" [syn: calm, calm down, quiet, tranquilize, tranquillize, tranquillise, quieten, lull, still] [ant: agitate, charge, charge up, commove, excite, rouse, turn on]
verb
Cause to be calm or quiet as by administering a sedative to; "The patient must be sedated before the operation" [syn: sedate, calm, tranquilize, tranquillize, tranquillise] [ant: arouse, brace, energise, energize, perk up, stimulate]

Definition of 'Tranquilize'

From: GCIDE
  • Tranquilize \Tran"quil*ize\, Tranquillize \Tran"quil*lize\, v. t. [imp. & p. p. Tranquilizedor Tranquilliized; p. pr. & vb. n. Tranquilizingor Tranquillizing.] [Cf. F. tranquilliser.] To render tranquil; to allay when agitated; to compose; to make calm and peaceful; as, to tranquilize a state disturbed by factions or civil commotions; to tranquilize the mind. [1913 Webster]
  • Syn: To quiet; compose; still; soothe; appease; calm; pacify. [1913 Webster] Tranquilizer