Etymology Inherited from Middle English sedatif, from Anglo-Norman sedatif, from Medieval Latin sēdātīvus, which itself likely influenced the modern spelling. By surface analysis, sedate + -ive.
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Medicine, Pharmacology, Sciences An agent or drug that sedates, having a calming or soothing effect, or inducing sleep.
Michael Jackson probably died after he rapidly injected himself with a dose of the surgical anesthetic propofol on top of a large dose of sedatives he swallowed when Dr. Conrad Murray was away, the defense’s propofol expert testified Friday. […] White also concluded that Jackson swallowed a large dose of lorazepam several hours earlier, which would have left "a very high concentration" of the sedative in his body.2011 October 28, Alan Duke, “Michael Jackson gave himself fatal overdose, expert says”, in CNN, archived from the original on 29 Dec 2016:
Etymology Inherited from Middle English sedatif, from Anglo-Norman sedatif, from Medieval Latin sēdātīvus, which itself likely influenced the modern spelling. By surface analysis, sedate + -ive.