Mag Dhubháin
Mag DHUBHÁIN—IV—Magwain, M'Gowane, Maguane, MacGuane, MacGuone, (MacGowan, Magowan); 'son of Dubhán' (diminutive of dubh, black); the name of an ancient family in Tirconnell, who were chiefs of Tir-Enda, in the barony of Raphoe; also found in Clare and Mayo. In the latter county it is always anglicised Magowan or MacGowan, which greatly obscures its origin.
Alphabetical Index to Irish Surnames