MacGregor is a Scottish surname. The name is Anglicised form of the Scottish Gaelic MacGriogair. The Gaelic name was originally a patronym, and means "son of Griogar". The Gaelic personal name Griogar is a Gaelicised form of the name Gregory. The surname is used by members of the Scottish clan Clan Gregor, also known as Clan MacGregor.
The surname was banned in Scotland several times prior to the 18th century, in an effort to clamp down on the unruly clan.