What is mcgrath name origin?

The surname McGrath is of Irish origin and is derived from the Gaelic Mac Craith, meaning "son of Craith". Craith was a personal name in ancient Ireland, and the Mac Craith sept was centred around County Waterford in the southeast of Ireland. The McGrath clan was one of the largest and most powerful in Ireland, with significant influence during the medieval period. The name has now spread throughout the world, particularly to the United States, Canada, Australia, and New Zealand.