#1 tranquillize v. [calm, calm down, quiet, tranquilize, tranquillise, quieten, lull, still] make calm or still; "quiet the dragons of worry and fear". wn
#2 tranquillize v. [sedate, calm, tranquilize, tranquillise] cause to be calm or quiet as by administering a sedative to; "The patient must be sedated before the operation". wn
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