An Etymological Dictionary of the German Language/schränken

by Friedrich Kluge

schränken, vb., ‘to cross, entwine, enclose with a railing, limit,’ from MidHG. schręnken, ‘to lay aslant, fence in, plait,’ OHG. skręnchen, ‘to lay aslant, deceive,’ MidE. schręnchen, ‘to cheat.’ The root implied is Teut. skrank, Aryan skrang (see Schrank), which is identical with the Aryan root skrak appearing in schräg.