Ó hAitheasa
Ó hAITHEASA—I—O Hahassie, O Hahesy, O'Hahasy, Hahasy, Hahessy, Ahessy; 'descendant of Aitheas' (pain, distress); the name of a family of Siol Anmchadha, in the south-east of Co. Galway. At the end of the 16th century, it was found chiefly in Tipperary and Waterford. It is now very rare.
Alphabetical Index to Irish Surnames