Heal
Old English hǣlan (in the sense ‘restore to sound health’), of Germanic origin; related to Dutch heelen and German heilen, also to whole.
wiktionary
From Middle English helen, from Old English hǣlan(“to heal, cure, save, greet, salute”), from Proto-West Germanic *hailijan, from Proto-Germanic *hailijaną(“to heal, make whole, save”), from Proto-Indo-European *koyl-(“safe, unharmed”).
See hele.
etymonline
heal (v.)
Old English hælan "cure; save; make whole, sound and well," from Proto-Germanic *hailjan (source also of Old Saxon helian, Old Norse heila, Old Frisian hela, Dutch helen, German heilen, Gothic ga-hailjan "to heal, cure"), literally "to make whole" (from PIE *kailo- "whole;" see health). Intransitive sense from late 14c. Related: Healed; healing.