O%27ryan Family History
O%27ryan Name Meaning
(Leinster) Anglicized form of Gaelic Ó Riagháin (modern Irish Ó Riain) ‘descendant of Rian, earlier Riaghán’, a personal name of uncertain etymology. See also Ryan. (Munster) Anglicized form of Gaelic Ó Maoilriain ‘descendant of Maoilriaghain’, a personal name meaning ‘follower of Riaghán’. (Connacht) Anglicized form of Gaelic Ó Ruaidhín ‘descendant of the little red one’, from a diminutive of ruadh ‘red’.
Source: Dictionary of American Family Names ©2013, Oxford University Press