Old English wealwian "to roll," from West Germanic *walwon, from PIE root *wel- (3) "to roll" (see volvox). Figurative sense of "to plunge and remain in some state or condition" is attested from early 13c. Related: Wallowed; wallowing. The noun is recorded from 1590s as "act of rolling;" 1841 as "place where an animal wallows."