- sedate (adj.)
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- "calm, quiet," 1660s, from Latin sedatus "composed, moderate, quiet, tranquil," past participle of sedare "to settle, calm," causative of sedere "to sit" (see sedentary). Related: Sedately.
- sedate (v.)
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- "treat with sedatives," 1945, a back-formation from the noun derivative of sedative (adj.). The word also existed 17c. in a sense "make calm or quiet." Related: Sedated; sedating.