MacGillean. From a Highland chieftain of the name of Gillean, who was the progenitor of this family. This Gillean was a celebrated warrior, and was called Gilleanni-Tuoidh, from his ordinary weapon, a battle-ax, which in the Gaelic is Tuoidh, which his descendants wear to this day in their crest, betwixt a laurel and a cypress branch. The posterity of this Gillean were therefore called Mac Gillean, in all ancient documents, and now of modern date McLeans. "Magh Leamhna," in the County of Antrim, the estate of the McLeans or Macklins.

Arthur, William (1857) An Etymological Dictionary of Family and Christian Names. New York: Sheldon, Blakeman. Public Domain.