This famous surname is of ancient Gaelic origin. It derives from the medieval Irish surname O'Gallchobhair, meaning the male descendant of Gallchobhair.This was a personal name composed of the elements gall, meaning foreign, and cabhair, help, suggesting that the original name holders were foreign mercenaries, possibly Welsh.he crest has a red crescent, and out of the horns, a serpent erect proper. The first recorded spelling of the family name is shown to be that of Teag O'Gallchobhair. This was dated 1350, in the Ancient Records of Tirconnell, County Donegal.