An Etymological Dictionary of the German Language/Rabe
Rabe, m., ‘raven,’ from the equiv. MidHG. rabe (rappe), OHG. rabo (*rappo), m., also MidHG. raben, OHG. raban, hraban, and MidHG. ram (mm), OHG. ram, hram (with mm for mn), m., ‘raven’; all these forms point to Goth. *hrabns. Comp. OIc. hrafn, AS. hrœfn, m., E. raven, Du. raaf, rave (comp. Rappe). The proper names Wolf-ram, OHG. Hraban, and ModHG. Rapp preserve the old variants. Perhaps these cognates with Lat. corvus, Gr. κόραξ, ‘raven,’ Lat. cornir, and Gr. κορώνη, ‘crow,’ belong to the same root; yet the Teut. form has a peculiar structure of its own, which, contrary to the usual assumption, presents some difficulties.