Ó Caiside
Ó CAISIDE—I—O Cashedy, O Cassidy, O Kesedy, Cassidy, Cassedy, Kessidy, &c.; 'descendant of *Caiside'; the name of a distinguished medical family in Fermanagh who were hereditary physicians to the Maguires. Branches of the family had settled in the midland counties before the end of the 16th century.
Alphabetical Index to Irish Surnames