"thing to sit on, act of sitting," c.1200, from O.N. sæti "seat, position," from P.Gmc. *sæt- (cf. O.H.G. saze, M.Du. gesaete "seat," O.H.G. gisazi, Ger. Gesäß "buttocks"), from PIE base *sed- "to sit" (see
sit). The verb is from 1577. Meaning "posterior