An Etymological Dictionary of the German Language/Annotated/Gau
Gau, masculine, from the equivalent Middle High German göu, gou, neuter, Old High German gęwi, gouwi, neuter, ‘district.’ According to Gothic gawi (gaujis), neuter, ‘scenery, country,’ we might have expected Old High German gęwi (gouwes), Middle High German göu (gouwes), since j after au becomes w without producing modification (compare Frau). Even now Gäu, neuter, is found in Bavarian, Suabian, and Swiss, but in the sense of ‘country’ opposed to town. The word is unknown to Scandinavian, and also to Saxon and English, in which Gau, as the second part of a compound name applied to a district, is met with only in the very earliest period; compare e.g. Anglo-Saxon œ́lge, ‘district of eels,’ Old Low German Pathergô, ‘Pader district’ (around Paderborn). The Modern High German word first obtained currency again in the last century as a result of the study of Old German (see Hort). No tenable root has yet been found.