Originally an Anglicized form of the ancient Irish male name Ceallach. It is now very widely used in the English-speaking world, mainly as a girl's name. This is a transferred use of the surname Ó Ceallaigh ‘descendant of Ceallach’.
German: from Middle High German hane ‘rooster’, hence a nickname for a conceited or sexually active man. In some instances it may have been a habitational name from a house bearing the sign of a rooster.