An Etymological Dictionary of the German Language/Hölle
Hölle, f., ‘hell,’ from the equiv. MidHG. hęlle, OHG. hęlla, f., from hallja; comp. Goth. halja, AS. and E. hell, OSax. hęlla; a common Teut. term applied by Christianity to ‘hades, infernum’; the Scand. hel shows that the earlier word upon which it is based was also used in prehistoric times for a heathen ‘infernum.’ Comp. also OIc. Hel, the goddess of the dead. It was possible for Christianity to adopt the old heathen word in all the Teut. languages; in this case it is quite unnecessary to assume the diffusion of a Goth. or other term (comp. Heide). It is usually connected with the root hel, hal, ‘to cover for concealment,’ hence Hölle, ‘the hiding-place.’ See hehlen, Hülle.