An Etymological Dictionary of the German Language/kerben
kerben, vb. ‘to notch,’ from the equiv. MidHG. kërben (with a str. partic. gekurben in Lower Rhen.); an orig. str. vb. with the graded forms kërfan, karf, kurbum, korban (comp. AS. čeorfan, E. to carve, Du. kerven); the final f of the stem kerf is attested by the MidHG. kërve, a variant of kërbe; Goth. *kaírfan is wanting. The root kerf is found also in Gr. γράφω, ‘to write,’ prop. ‘to cut in, scratch’ (comp. HG. reißen with E. to write), which with Teut. kerf points to a Sans. root *gṛph.