An Etymological Dictionary of the German Language/Haber
Haber (UpG.), m., ‘oats, from the equiv. MidHG. haber, habere, m., OHG. habaro, m. The form Hafer first occurs in ModHG.; like Roggen, it is derived from LG.; OLG. haƀoro, havoro (now hawer), Du. haver. Also allied to OSwed. hafre, hagre, and farther to Finn. kakra, borrowed from Teut. In E. the word is wanting, but is found a few times in MidE., which, like Northern E. (haver), borrowed it from Scand. The E. term is oats, from AS. âta (yet Scotch haver occurs even in the MidE. period). In investigating the origin of the G. cognates, the g in OSwed. hagre (Finn. kakra) must be taken into account. The usual derivation from OIc. hafr, AS. hœfer, m., ‘he-goat’ (Lat. caper, Gr. κάπρος, comp. Habergeiß), is therefore impossible, especially since this word belongs to the dialects in which Hafer is wanting; Hafer too must have been the favourite food of the goat ere it could be thus named. Perhaps Gr. κάχρυς, ‘parched barley’ (Aryan base khaghru-), or Lat. avena, ‘oats’ (Aryan base khaghwes), are primit. allied.