Family name origins & meanings
- Irish : (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.
- Irish : (Munster) Anglicized form of Gaelic Ó Maoilriain ‘descendant of Maoilriaghain’, a personal name meaning ‘follower of Riaghán’.
- Irish : (Connacht) Anglicized form of Gaelic Ó Ruaidhín ‘descendant of the little red one’, from a diminutive of ruadh ‘red’.