An Etymological Dictionary of the German Language/Falter

by Friedrich Kluge

Falter, m., simply ModHG., ‘butterfly’; the MidHG. term is vîvalter (corrupted also into zwivalter), ‘butterfly,’ from which the ModHG. word has been corrupted by connecting it with falten. But MidHG. vîvalter is based upon an OTeut. term for ‘butterfly,’ which may have been *feifaldrô in Goth.; comp. OHG. fîfaltra, OSax. fîfoldara, AS. fîfealde, OIc. fifrilde, ‘butterfly’; akin to Du. vijfwouter, ‘a sort of butterfly.’ The origin of this term is not yet established, although it is probably a reduplicated form like beben and zittern.