An Etymological Dictionary of the German Language/Flügel

by Friedrich Kluge

Flügel, m., ‘wing, leaf (of a folding door), aisle, grand piano,’ from the equiv. MidHG. vlügel, m..; comp. Du. vleugel, ‘wing’; a late derivative of fliegen. Strange to say, a common Teut. word is wanting. For an OAryan root, ‘to fly,’ see Feder (also Farn).