An Etymological Dictionary of the German Language/wispeln

by Friedrich Kluge

wispeln, vb., ‘to whisper,’ from the equiv. MidHG. wispeln, OHG. wispalôn, hwispalôn. Also in ModHG. only, wispern (properly perhaps a LG. word), corresponding to AS. hwisprian, E. to whisper. These intensive forms seem to be based on an onomat. root hwī̆s (hais), to which also heiser is usually referred.