Ó Ruaidhín
Ó RUAIDHÍN—I—O Ruyne, O Royn, O Roen, Rouine, Royan, Rowen, (Ruane, O'Ryan, Ryan); 'descendant of Ruaidhín' (diminutive of ruadh, red); the same as Ó Ruadháin, which see, both forms being used by the same family, and equally common in Connacht. Some of the name have been long settled in Leinster.
Alphabetical Index to Irish Surnames