An Etymological Dictionary of the German Language/offen

by Friedrich Kluge

offen, adj., from the equiv. MidHG. offen, OHG. offan, adj., ‘open’; it has the same meaning in all the Teut. languages except. Goth., where *upans is wanting. Comp. OIc. openn, AS. and E. open, Du. open, OSax. opan; the adj. seems similar in form to a partic., but the primit. verb cannot be adduced. It is also doubtful whether auf, OSax. upp, Goth. iup, is allied, so that offen would mean lit. ‘drawn up.’