McCarthy is a surname originating from the Irish noble McCarthy Clan of Cork County, Ireland.
The name has spread throughout the world and is most often found in the Americas, where over 57% of individuals with the surname McCarthy are located.
[1] The surname, meaning "son of Cárthach" originated in Ireland.
[2] Commons variants of the name include McCarty and MacCarthy.
Sixty percent of people with the surname in Ireland itself originate from Cork County, where the family was very powerful in the Middle Ages.