An Etymological Dictionary of the German Language/Annotated/Föhn

by Friedrich Kluge

Föhn, masculine, a Swiss word, ‘humid and tempestuous south wind’; the corresponding term in Middle High German is wanting, though Old High German fônna, feminine (fônno, masculine), ‘rainy wind, whirlwind,’ is recorded; from Latin favonius (the intermediate form is faunio-), whence also Italian favonio, Rhæto-Romance favuogn.