- serene (adj.)
- mid-15c., "clear, calm," from Latin serenus "peaceful, calm, clear" (of weather), figuratively "cheerful, glad, tranquil," of uncertain origin; perhaps from a suffixed variant of PIE *ksero- "dry," source of Greek xeros "dry" (see xerasia). In English, applied to persons since 1630s. Related: Serenely.
