An Etymological Dictionary of the German Language/Annotated/hantieren
hantieren, verb, from the equivalent late Middle High German hantieren, ‘to trade, sell’; not a derivative of Hand, meaning ‘to handle,’ because in that case we should expect nd for nt in Middle High German and Modern High German, but from French hanter, ‘to haunt, frequent,’ which found its way from Middle Dutch into the Modern Teutonic dialects. It is curious to observe in how many ways obscure words have been corrupted in German. Compare the earlier spelling handthieren.