Meide ind Eoin, and Meide in Togmail: places in or near the Boyne, in the County Louth
Midluachair: Slige Midluachra, the name of the highroad east of Armagh, leading north from Tara to Emain and into the north of Ireland
Mil: the legendary progenitor of the Milesians (See Maic Miled)
Miliuc: a river in Conalle Murthemni
Moduirn: see Sliab Moduirn
Moin Coltna: a bog between Slieve Bawne and the Shannon
Moraltach: great grandfather of Cuchulain
Morann: a famous judge
Morrigan: the war-goddess of the ancient Irish, "monstrum in feminae figura" (pronounced More-reegan)
Mossa: a territory, the southern part of which must have been in the barony of Eliogarty, not far from Cashel, in the County Tipperary