An Etymological Dictionary of the German Language/grimm

by Friedrich Kluge

grimm, adj., ‘fierce, wrathful, furious,’ from MidHG. grim, grimme, OHG. grim, grimmi, ‘unfriendly, frightful, savage’ (to which ModHG. grimmig, MidHG. grimmec and OHG. grimmig are allied). Corresponding to OSax. and AS. grim(mm), E. grim, Du. grimmig, OIc. grimmr, Goth. *grimma-; allied to ModHG. gram, root grem (by gradation gram). —