An Etymological Dictionary of the German Language/Annotated/Haber
Haber (Upper German), masculine, ‘oats, from the equivalent Middle High German haber, habere, masculine, Old High German habaro, masculine. The form Hafer first occurs in Modern High German; like Roggen, it is derived from Low German; Old Low German haƀoro, havoro (now hawer), Dutch haver. Also allied to Old Swedish hafre, hagre, and farther to Finnish kakra, borrowed from Teutonic. In English the word is wanting, but is found a few times in Middle English, which, like Northern English (haver), borrowed it from Scandinavian. The English term is oats, from Anglo-Saxon âta (yet Scotch haver occurs even in the Middle English period). In investigating the origin of the German cognates, the g in Old Swedish hagre (Finnish kakra) must be taken into account. The usual derivation from Old Icelandic hafr, Anglo-Saxon hœfer, masculine, ‘he-goat’ (Latin caper, Greek κάπρος, compare 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 Greek κάχρυς, ‘parched barley’ (Aryan base khaghru-), or Latin avena, ‘oats’ (Aryan base khaghwes), are primitively allied.