Ó hAinchín
Ó hAINCHÍN—I—O Hanhine, O Hanhin, Hanneen, Hannin, Hannen, (Hannan, Hannon); 'descendant of *Ainchín' (perhaps for Ainghein, unborn); the name of a family of Siol Anmchadha, in south-east of Co. Galway. It was common at the end of the 16th century in many parts of Connacht and Munster. See also Ó hAinnín. MacFirbis mentions Ó hAinghein as a Connacht surname.
Alphabetical Index to Irish Surnames