O'Keeffe (Irish: Ó Caoimh) is an Irish Gaelic clan based most prominently in what is today County Cork, particularly around Fermoy and Duhallow. The name comes from caomh, meaning "kind", "gentle", "noble" Some reformed spellings present it as Ó Cuív and the feminine form of the original is Ní Chaoimh, as the primary sept of the Eóganacht Glendamnach, the family were once Kings of Munster from the 6th to the 8th centuries.