An Etymological Dictionary of the German Language/Annotated/Riese

by Friedrich Kluge

Riese, masculine, ‘giant,’ from the equivalent Middle High German rise, Old High German risi, riso, masculine; compare Old Saxon wrisi-lîc, ‘gigantic,’ Old Low German wrisil, Dutch reus, ‘giant.’ Gothic *wrisi-, or rather *wrisjan-, is wanting. It seems primitively allied to Sanscrit vṛšan, ‘mighty, manly, strong,’ to which Old Irish fairsing, ‘great, powerful,’ is also probably akin.