An Etymological Dictionary of the German Language/Annotated/schleißen
schleißen, verb, ‘to slit, split, gash,’ from Middle High German slîȥen, Old High German slîȥan, ‘to split, tear to pieces, wear out’; corresponding to Old Saxon slîtan, ‘to tear to pieces,’ Dutch slijten, ‘to wear out,’ Anglo-Saxon slîtan, ‘to tear to pieces,’ to which English to slit is allied, Old Icelandic slíta, ‘to tear to pieces.’ The Teutonic root slī̆t, ‘to tear to pieces’ (Gothic *sleitan), from pre-Teutonic slī̆d, has not yet been found in the non-Teutonic languages. See schlitzen, the intensive form. Schleißen, weak verb, as the factitive of the strong verb, is Middle High German and Old High German sleiȥen, sleitzen, ‘to tear to pieces, split.’