súsvort

f. the nightingale; einn fugl þann er heitir philomela á Látinu en á Norrænu heitir súsvort, sumir kalla ok niktigalu, Barl. 39: the word is obsolete in Icel., and the passage in Barl. stands alone in the old literature; not even does the Edda (Gl. in the list of birds) record this word; but it is preserved in provincial Norse sysvorta (sisvorta, svisvorta) = turdus torquatus, the ring ousel, Ivar Aasen: the etymology is quite uncertain.