tranquilizer has definitions from the fields of medicine,pharmacology
1
[ noun ] (medicine,pharmacology) drug that reduces nervous tension and gives peace of mind without producing sleep
2
[ noun ] (medicine,pharmacology) a drug used to reduce stress or tension without reducing mental clarity

Used in print

(E. Gellhorn, "Prolegomena to a theory of the emotions"...)

The former comprise analeptic and psychoactive_drugs , the latter the tranquilizers .

The emotional_states produced by drugs influence the cortical_potentials in a characteristic manner ; synchrony prevails in the EEG of the experimental animal after administration of tranquilizers , but asynchrony after application of analeptic and psychoactive_drugs .

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