A terrifying female sea-monster that at one time inhabited Lough Rudraige (Dundrum Bay). It is said to have been killed by Fergus mac Léti, a mythical king of Ulster, who wore magic shoes, obtained from Iubdán, that enabled him to walk on water. After the battle, which lasted for two days and which turned the sea red with blood, Fergus himself died of exhaustion.

In later texts the creature is called Sínach ("Stormy One"). See also Caoránach, Oilliphéist.



  • The Death of Fergus mac Leide. Retrieved August 31, 2006.
  • MacKillop, James. (2004). Dictionary of Celtic Mythology. New York: Oxford University Press, Inc.