tranquilizer

n. sedative drug

A sedative is a substance that depresses the central nervous system (CNS), resulting in calmness, relaxation, reduction of anxiety, sleepiness, and slowed breathing, as well as slurred speech, staggering gait, poor judgment, and slow, uncertain reflexes. Sedatives may be referred to as tranquilizers, depressants, anxiolytics, soporifics, sleeping pills, downers, or sedative-hypnotics. Sedatives can be abused to produce an overly-calming effect (alcohol being the classic and most common sedating drug). At high doses or when they are abused, many of these drugs can cause unconsciousness (see hypnotic) and even death.
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n. tranquillizer, tranquilizer

(n.)
Alt. of Tranquillizer
  

Noun
1. a drug used to reduce stress or tension without reducing mental clarity
(synonym) tranquillizer, tranquilliser, antianxiety agent, ataractic drug, ataractic agent, ataractic
(hypernym) psychotropic agent
(hyponym) major tranquilizer, major tranquillizer, major tranquilliser, antipsychotic drug, antipsychotic agent, antipsychotic, neuroleptic drug, neuroleptic agent, neuroleptic
(derivation) calm, calm down, quiet, tranquilize, tranquillize, tranquillise, quieten, lull, still