ATARACTIC
ataractic, ataraxic, sedative, tranquilizing, tranquillizing, tranquilising, tranquillising
(adjective) tending to soothe or tranquilize; “valium has a tranquilizing effect”; “took a hot drink with sedative properties before going to bed”
tranquilizer, tranquillizer, tranquilliser, antianxiety agent, ataractic drug, ataractic agent, ataractic
(noun) a drug used to reduce stress or tension without reducing mental clarity
Source: WordNet® 3.1
Etymology
Adjective
ataractic (comparative more ataractic, superlative most ataractic)
(pharmaceutical effect) That has a tranquilizing effect
Noun
ataractic (plural ataractics)
(pharmaceutical drug) A drug that is used to tranquilize; a tranquilizer.
Source: Wiktionary