An Etymological Dictionary of the German Language/Annotated/Fitze
Fitze, feminine, ‘knot of yarn, skein, wrinkle,’ from Middle High German vitze, Old High German fizza, feminine, ‘a number of reeled threads tied together, skein, yarn’; akin to Old Icelandic fǫt, ‘clothes,’ Middle High German vaȥȥen, ‘to dress,’ root fat, fet? ‘to spin’? ‘to weave’?. Yet it is more closely connected with Old Saxon fittea, Anglo-Saxon fitt, ‘chapters, divisions in poems.’