1590s, "remaining in one place," from Middle French sédentaire (16c.) and directly from Latin sedentarius "sitting, remaining in one place," from sedentem (nominative sedens), present participle of sedere "to sit; occupy an official seat, preside; sit still, remain; be fixed or settled," from PIE root *sed- (1) "to sit" (cognates: Sanskrit a-sadat "sat down," sidati "sits;" Old Persian hadis "abode;" Greek ezesthai "to sit," hedra "seat, chair, face of a geometric solid;" Old Irish suide "seat, sitting;" Welsh sedd "seat," eistedd "sitting;" Old Church Slavonic sežda, sedeti "to sit;" Lithuanian sedmi "to sit;" Russian sad "garden," Lithuanian soditi "to plant;" Gothic sitan, Old English sittan "to sit;" see sit). Of persons, the sense "not in the habit of exercise" is recorded from 1660s.