Clans and Families of Ireland (The
Heritage and Heraldry of Irish Clans and Families) by John
Grenham forword by Donal Begley (Chief Herald of Ireland) states:
(pg. 118) Hegarty: "In Irish the Surname is O hEigceartaigh, from
eigceartach, meaning unjust'. The name appears to have arisen first in
the area now divided between counties Derry and Donegal, where the O
hEigceartaigh were a branch of the Cinel Eoghaain, that large group of
families calming descent from Eoghan, one of the sons of Niall of the
Nine Hostages, the fifth-century monarch who supposedly kidnapped St
Patrick to Ireland. However, today the surname is much more common in
Co. Cork (O') Hegartys were claimed as a branch of the more historically
prominent northern family, but ecertach was a common personal name in
Munster, and it seems more likely that the surname arose separately
there. At any rate, O'Hegartys are recorded in west Cork as early as
the thirteenth century, and remain strongly associated with the area."
The Surnames of Ireland by Edward
MacLysaght states:
(Pg. 142) " (O) Haggerty a variant of Hegarty"
(pg. 153) "O Hegarty O hEigceartaigh (eigceartach, unjust). Primarily
an Ulster sept. There was also one of the same name in Munster, a
branch of the Eoghanacht."
