Ó Gáibhtheacháin
Ó GÁIBHTHEACHÁIN—I—Gavaghan, Gavahan, Gavagan, Gavacan, Gavigan, Gaffikan, Gaughan, Gahan; 'descendant of Gáibhtheachán' (diminutive of gaibhtheach, plaintive, querimonious); the name of a branch of the Ui Fiachrach who were anciently chiefs of Calraighe Muighe hEleog, a district nearly co-extensive with the parish of Crossmolina, in Co. Mayo; now pronounced Ó Gácháin, and very common in Mayo and Sligo.
Alphabetical Index to Irish Surnames