An Etymological Dictionary of the German Language/piepen

by Friedrich Kluge

piepen, vb., ‘to pipe, pip, chirp,’ from LG. piepen, which, like Lat. pipare, is an onomatopoetic form; comp. the equiv. E. to peep, Gr. πιππίζειν, Fr. pépier, Ital. pipillare, Lith. pýpti, Czech pípati.