[Ir., teacher (?)].
Elder daughter of the legendary king Túathal Techtmar whose unhappy marriage to Eochaid (8) brought humiliation to his kingdom, Leinster. Preferring Fithir's comely younger sister Dáirine, Eochaid used deceit to marry her as well; both daughters died, Fithir of shame and Dáirine of grief, or in other texts both of shame. Túathal waged war upon Eochaid, killing him and forcing Leinstermen to pay the heavy bórama tribute.