An Etymological Dictionary of the German Language/Annotated/Böhnhase
Böhnhase, masculine, ‘bungler, clumsy workman,’ first found in Modern High German; generally asserted to be a popular corruption of Greek βάναυσος, which means ‘artisan;’ but it is inexplicable how the Greek word found its way into popular speech. It is more probably of real German origin, although the primary meaning cannot be got at; we must begin with the fact that the word is native to Low German, and is chiefly used in Tailors' Guilds. We must probably regard hase as a Low German form for Hose (see Aberglaube, Adebar). Böhn is generally considered to be a Low German word for Bühne, ‘garret’; hence Böhnhase is perhaps ‘one who makes breeches in the garret, petty tailor’ (opposed to one whose workroom is on the first floor).