An Etymological Dictionary of the German Language/zer-
zer-, prefix from MidHG. zer- (MidG. zur- and zu-), OHG. zir-, zar-, zur-; a common West Teut. verbal prefix, meaning ‘asunder’; comp. OSax. ti, AS. tô. In Goth. only twis- occurs as a verbal prefix in twisstandan, ‘to separate’; the nominal Goth. prefix tuz- (OHG. zûr-, OIc. tor-) corresponds to Gr. δυς-, Sans. dus, ‘bad, difficult.’