MacCarthy MacCarthy MacCarthy (Irish: Mac Cárthaigh), also spelled Macarthy, McCarthy or McCarty, is a Gaelic Irish clan originating from Munster, an area they ruled during the Middle Ages. It was and continues to be divided into several great branches. The MacCarthy Reagh, MacCarthy of Muskerry, and MacCarthy of Duhallow dynasties were the three most important of these, after the central or MacCarthy Mór line. Their name, meaning "son of Cárthach" (whose name meant "loving"), is a common surname that originated in Ireland. As a surname, its prevalent spelling in the English language is McCarthy. Several variants are found, such as McCarty
Irish people used. While both "Mac" and "Ó'" prefixes are Gaelic in origin, "Mac" is more common in Scotland and in Ulster than in the rest of Ireland; furthermore, "Ó" is far less common in Scotland than it is in Ireland. The proper surname for a woman in Irish uses the feminine prefix nic (meaning daughter) in place of mac. Thus a boy may be called Mac Domhnaill whereas his sister would be called Nic Dhomhnaill or Ní Dhomhnaill – the insertion of 'h' follows the female prefix in the case of most consonants (bar H, L, N, R, & T). A