heavenly hall in which Odin receives the souls of heroes slain in battle, 1696 (in Archdeacon Nicolson's "English Historical Library"), from Old Norse Valhöll "hall of the battle-slain;" first element from valr "those slain in battle," from Proto-Germanic *walaz (source also of Old English wæl "slaughter, bodies of the slain," Old High German wal "battlefield, slaughter"), from PIE root *wele- (2) "to strike, wound" (source also of Avestan vareta- "seized, prisoner," Latin veles "ghosts of the dead," Old Irish fuil "blood," Welsh gwel "wound"). Second element is from höll "hall," from PIE root *kel- (1) "to cover, conceal, save." Reintroduced by 18c. antiquaries. Figurative sense is from 1845.

Proto-Indo-European root meaning "to cover, conceal, save."

It forms all or part of: Anselm; apocalypse; Brussels; caliology; Calypso; calyx; ceiling; cell; cellar; cellular; cellulite; cellulitis; cilia; clandestine; cojones; coleoptera; color; conceal; eucalyptus; hall; hell; helm (n.2) "a helmet;" helmet; hold (n.2) "space in a ship below the lower deck;" hole; hollow; holster; housing (n.2) "ornamental covering;" hull (n.1) "seed covering;" kil-; kleptomania; occult; rathskeller; supercilious; Valhalla; William.

It is the hypothetical source of/evidence for its existence is provided by: Sanskrit cala "hut, house, hall;" Greek kalia "hut, nest," kalyptein "to cover," koleon, koleos "sheath," kelyphos "shell, husk;" Latin cella "small room, store room, hut," celare "to hide, conceal," clam "secret," clepere "to steal, listen secretly to;" Old Irish cuile "cellar," celim "hide," Middle Irish cul "defense, shelter;" Gothic hulistr "covering," Old English heolstor "lurking-hole, cave, covering," Gothic huljan "to cover over," hulundi "hole," hilms "helmet," halja "hell," Old English hol "cave," holu "husk, pod;" Old Prussian au-klipts "hidden;" Old Church Slavonic poklopu "cover, wrapping."