Boy name origins & meanings Scandinavian : Day Boy name variations Dag Dagmar Dagney Dagny Dagget Dailey Daily Daley Day Dayton Daymond Daeg Family name origins & meanings Irish : Anglicized form of Gaelic Ó Duibhginn ‘descendant of Duibhgeann’, a byname from dubh ‘black’ +ceann ‘head’, ‘chief’.