An Etymological Dictionary of the German Language/Rücken

by Friedrich Kluge

Rücken, im., ‘back, rear, ridge,’ from the equiv. MidHG. rücke, OHG. rucki, earlier hrukki, m. (Goth. *hrugja- is to be assumed); comp. the equiv. OSax. hruggi, Du. rug, AS. hrycg, E. ridge, OIc. hryggr. Gr. ῥάχις, ‘back,’ is not allied, because krakjó- is the OAryan form for Rücken. It is more probably related to OIr. crocen, ‘skin, back,’ and the Sans. root kruñc, ‘to bend,’ so Rücken may have been named from its flexibility. See zurück.—