An Etymological Dictionary of the German Language/Annotated/feucht
feucht, adjective, ‘moist, damp, humid,’ from the equivalent Middle High German viuhte, Old High German fûhti, fûht, (Gothic *fûhtu- is wanting). The adjective is West Teutonic; compare Low German fucht, Anglo-Saxon fûht, English obsolete, Dutch vochtig, ‘damp.’ An allied root (pū̆k), qū̆k, quak, is assumed for Old Slovenian kysnąti, ‘to grow sour,’ kvasiti, ‘to acidify,’ which are scarcely connected with this word.