An Etymological Dictionary of the German Language/Annotated/feiern
feiern, ‘to celebrate,’ from Middle High German vîren, Old High German fîrrôn, fîrôn, ‘to celebrate, keep a festival,’ formed from Latin feriari. The borrowed word is found in the Teutonic languages of Middle Europe (Dutch vierdag, Old Frisian fîra), but is wanting in English and Scandinavian. The Romance languages preserve Latin feriae in the sense of ‘fair’; compare Italian fiera, French foire (hence English fair). Compare Messe and Fest. —