O'Casey

O'Casey
Family name
Meaning	descendant of Cathasach (vigilant or watchful)
Region of origin	Ireland
Language(s) of origin	Old Irish (Anglicized)
Related names	O'Cathasaigh Casey (disambiguation) MacCasey

O'Casey is a common variation of the Gaelic cathasaigh, meaning vigilant or watchful, with the added anglicized prefix O' of the Gaelic Ó, meaning grandson or descendant. At least six different septs used this name, primarily in the Counties of Cork and Dublin.

People with the surname O'Casey include:

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