Grannan Family History
Grannan Name Meaning
Irish:: shortened form of MacGrannan an Anglicized form of Gaelic Mag Raghnainn a form of Mac Raghnaill ‘son of Raghnall’ a Gaelic form of the Old Norse personal name Rǫgnvaldr ‘ruler of the gods’ cognate with Reynolds . shortened form of Ó Grianáin see Greenan .
Source: Dictionary of American Family Names 2nd edition, 2022