The act of calming a person or animal, or putting them to sleep, using a drug. / The act of making someone or something tranquil.

Of a drug: having the effect of calming a person or animal, or putting them to sleep; sedating, sedative. / (literary) Having the effect of making someone or something tranquil; calming, soothing.

present participle of tranquilize

simple past tense and past participle of tranquillize

Free from emotional or mental disturbance. / Calm; without motion or sound.

US standard spelling of tranquillity.

Alternative spelling of tranquilize

The state of being tranquil; peacefulness, the absence of disturbance or stress; serenity; calm.

That which tranquillizes or soothes. / (pharmacology) A drug used to reduce anxiety or tension.

plural of tranquillizer