Family History and Genealogy Resources by Surname
Menai Surname Origin
(Origin Welsh) So called from Menai, a strait which divides the island of Anglesea from the coast of Wales. The Mena or Mona, worshiped by the Sequani, was the moon. The Gaels blessed the beams of this luminary that saved them from the danger of precipices, and Augustine says that the Gaelic peasants invoked Mena for the welfare of their women.
Source: An Etymological Dictionary of Family and Christian Names With an Essay on their Derivation and Import; Arthur, William, M.A.; New York, NY: Sheldon, Blake, Bleeker & CO., 1857.
Menai Surname Meaning and Family Facts
There is more to Menai family history than the origin of your surname:
A Menai Family History Thought:
'Those who forget their past are destined to repeat it.' --Robert A. Heinlein