Family History and Genealogy Resources by Surname
Tiernay Surname Origin(Origin Gaelic) Tighearna, a lord, a judge, a landed proprietor. See Tournay
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.
Tiernay Surname Meaning and Family Facts
There is more to Tiernay family history than the origin of your surname:
A Tiernay Family History Thought:
'Those who forget their past are destined to repeat it.' --Robert A. Heinlein