An Etymological Dictionary of the German Language/Schwan
Appearance
Schwan, m., ‘swan,’ from the equiv. MidHG. swane, swan, m., OHG. swan, m. (swana, f.); corresponding to Du. zwaan, AS. swǫn, E. swan, OIc. svanr, m., ‘swan’; Goth. *swans is by chance not recorded. Probably allied to the Sans. root svan, ‘to rustle, resound’ (comp. Hahn, allied to Lat. canere), Lat. sonare (for *svonare); prop. only of the singing swan?.