De Canntún
de CANNTÚN—XI—de Cauntoun, de Caunton, de Canton, Canton, Candon and Condon; Norman 'de Countyntoun,' 'de Cauntyton,' 'de Caunteton,' i.e., of C---------------, probably the present parish of Canton in Glamorganshire; an old Norman surname, sometimes anglicised Canton and Candon, but generally corrupted to Conndún (pronounced locally Cúnún) and anglicised Condon. The Condons are a well-known family in Cork, Waterford and Limerick who formerly possessed considerable property in the neighbourhood of Mitchelstown, from one of whom that town got its name.
Alphabetical Index to Irish Surnames