An Etymological Dictionary of the German Language/Annotated/Wahnsinn

by Friedrich Kluge

Wahnsinn, masculine, ‘frenzy, madness, delirium.’ It has properly no connection whatever with the preceding word; it first occurs in Modern High German, and is an imitation of the earlier Wahnwitz, masculine, ‘delirium,’ which is based on Middle High German wănwitzec, wănwitze, Old High German wănawizzi, adjective, ‘unintelligible, void of understanding.’ Wahnwitz is the sole relic of an old method of forming compounds with wăna-, ‘wanting,’ which is especially preserved in Scandinavian; compare also Old High German wanaheil, ‘sickly,’ literally perhaps ‘deficient in health’; thus too Old High German wanawizzi, ‘deficient in sense.’ Gothic wans, ‘deficient, lacking,’ Old Icelandic vanr, ‘lacking,’ is an old participle with the suffix ana, from the Aryan root ū̆, ‘to be empty,’ from which öde is derived; compare the Zend root û, ‘to want,’ Sanscrit ûna, ‘wanting,’ and Old High German wanôn, ‘to diminish.’