Family name origins & meanings
- Irish : reduced Anglicized form of Gaelic Ó Grúgáin ‘descendant of Grúgán’, a personal name from a diminutive of grúg ‘anger’, ‘fierceness’.
- Irish : reduced Anglicized form of Gaelic Ó Gruagáin ‘descendant of Gruagán’, a personal name from a diminutive of gruag ‘hair’. The patronymic form Mac Gruagáin (Anglicized McGrogan) is much rarer.