An Etymological Dictionary of the German Language/Annotated/Hacke
Hacke, feminine, ‘heel,’ properly a Middle German and Low German word (in Upper German Ferse); compare Dutch hak; not recorded in Middle High German, but it occurs once in the transition period from Old High German to Middle High German (hachun, ‘heels’); usually derived from hacken. On account of its meaning, it is more probably related to Dutch hiel, Anglo-Saxon hôh, ‘heel,’ hêla, feminine (for *hôhila), English heel, and the equivalent Scandinavian hœ̂ll, masculine.