AL-yil mahk MAH-ta
King consort of Connacht and Medb's husband, whose boast of equal wealth with his wife triggers the Táin Bó Cúailnge.
Ailill rules Connacht jointly with Medb from Cruachan, and it is his one advantage in their otherwise equal wealth — the bull Finnbennach — that wounds Medb's pride enough to launch the war for Ulster's rival bull. Through the Táin he rides alongside Medb, though the text repeatedly makes clear that the campaign, and its cunning, are hers more than his.
Ailill's own jealousy surfaces elsewhere in the wider tradition, most notably in tales of Medb's affairs with other men, including Fergus mac Róich during the exiled Ulster hero's time in Connacht.