Ó Creacháin
Ó CREACHÁIN, Ó CRÉACHÁIN—I—O Creghan, Creaghan, Crehan, (Creaton), Crean; 'descendant of Creachán' (diminutive of creach, or créach, blind); sometimes corrupted to Ó Gréacháin; the name of a branch of the Ui Fiachrach who were formerly seated in Tirawley, Co. Mayo. See Ó Críocháin.
Alphabetical Index to Irish Surnames