1 Sometimes Mugain Mór [Ir., great]. Territorial goddess of the south of Ireland who is reputed to have given birth to a trout. She appears to be identical with the better-known Mór Muman.
2 Strumpet wife of Conchobar mac Nessa, king of Ulster, daughter of Eochaid Feidlech, sister of Medb. In an often repeated episode, she and her maidens strip naked before Cúchulainn as he is returning from battle on his way to Emain Macha; though this is done ostensibly to stifle his battle fever, he is so consumed with passion upon seeing the women that it takes three vats of icy water to cool him down. Later she is caught in adultery with Áed (9), a court poet. Conchobar sentences Áed to death by drowning, but he has the power to dry up any lake with a spell, all except Lough Laíg, near the house of Lóegaire Búadach. In coming to Áed's help, Lóegaire himself is killed. In earlier Ulster stories Conchobar's wife is Eithne Aittencháithrech. See EITHNE (5).
3 Adulterous wife of Diarmait mac Cerbaill. Her co-respondent, Flann mac Díma, suffers more for their sin. Flann's house is burned and he is later drowned. This in turn brings about Diarmait's death. She is the mother of Áed Sláine, ancestor of the people of Brega.
4 Mother of St Cuimmíne, who begot him in incest. Her name appears in the quatrain, ‘This Mugain was his mother, he to her was a brother.’