Costello (surname) to a Gaelic translation of Jocelyn, Jocelyn d'Angulo's given name. In fact, MacOisdealbhaigh is the Gaelic translation of his brother Hostilo (or Hostilio) d'Angulo's first name. Oisdealbh is a much more obvious translation of Hostilo. It is Hostilo's descendants who would bear the surname Mac Oisdealbhaigh (son of Oisdealbh or Hostilo). The surname would later be anglicized to Costello, Costelloe, and Costellow. Gilbert d'Angulo is also sometimes listed as the son of Jocelyn d'Angulo in error. Gilbert d'Angulo is the father of both Jocelyn and Hostilo. It occasionally has been adopted as a pseudonym or stage name by famous people
Kennedy (surname) Kennedy (surname) Kennedy, alternately O'Kennedy and Kennedie, is a surname of Irish and Scottish origin that has also been used as a given name. There have been several different etymologies given for the surname. One is that the name is an Anglicisation of "Ó Cinnéide", meaning "grandson of "Cinnédidh"" or "grandson of "Cinnéidigh"", with both of these personal names meaning "helmet headed." "Ceanéidigh" could be related to the old Gaelic name "Cennétig", which is known from Cennétig Mac Lorcáin, the father of the Irish high king "Brian mac Cennétig", who himself was also known as "Brian Bóruma" or Brian Boru.