O'Fahey (Irish: '''Ó Fathaigh''') is an anglicised form of Ó Fathaigh. The patronym means "descendant of Fathaigh", whose name means "base" or "foundation".[1] Cormac Ó Fathaigh is the first recorded bearer with the surname and is the purported ancestor of any Ó Fathaigh descendants. The surname largely became Fahey, with many variations.
Anglicised versions of the surname: