Fenian cycle fen'-ee-uhn The Fenian cycle is a body of early Irish heroic tales centering on the exploits of Finn McCool and the Fianna, bands of warriors known as Fenians. Other characters include Finn's son Ossian, Ossian's son Oscar, and Diarmuid and Grania, young lovers who are pursued by Finn, Grania's fiance. Diarmuid, Grania, and Finn are analogous to another famous trio, Tristan, Isolde, and King Marc of the Arthurian legends. DAVID H. GREENE