Comartún
COMARTÚN—XI—Comerton, Comerford, etc.; i.e., 'of Comberton,' a parish in Cambridgeshire, if not 'of Comberford,' a village in Staffordshire. The Irish form would seem to point to the former as the origin, but compare with Rostún for Rochford. The Comerfords, as they are usually called, are an old and respectable family in Kilkenny and Waterford. The head of the family was Baron of Danganmore.
Alphabetical Index to Irish Surnames