Recorded in several forms including O'Rafferty, Rafferty, McGroarty, and McGrorty, this notable Irish surname much associated with the west of Ireland, derives from the pre 10th century Old Gaelic "O'Raithbheartaigh". This translates as "prosperity wielder" from the elements "rath", meaning prosperity, and "beartaigh", to brandish or wield. Traditionally, Irish family names are taken from the heads of tribes, or revered elders, and are usually prefixed by "Mac", denoting "son of", or "O", meaning male descendant of. The great O'Raithbheartaigh sept belonged to the Ulster county of Donegal where they were co-arbs of St. Columcille on Tory island. Co-arb families held church property from generation to generation, and generally maintained a priest. The Sligo branch of this family was known as "one of the seven pillars of Skreen", Skreen being a coastal parish in north County Sligo. A further early form of the name, "Mac Robhartaigh", now McGroarty is etymologically distinct from the "O'Raithbheartaigh", and translates as "flood-tide"; hence, presumably the two fish on the Rafferty coat of arms as since the 15th Century, both names being treated as the same. Early examples of the surname recording include: Maeve McGroarty, the daughter of Teag McGroarty, who was christened at Templemore, County Derry, on December 4th 1656, whilst Ann Rafferty, aged 29 years, embarked from the city of Newry on the ship "Brothers of Liverpool" bound for New York on April 23rd 1846. She was escaping from what became known as the Irish Potato famine, of 1846 - 1848. The first recorded spelling of the family name is shown to be that of Dermot O'Raighbheartaigh, abbot of Durrow. This was dated 1090, in the "Annals of the Four Masters", during the reign of High Kings of Ireland "with opposition", 1022 -1166.