Dom is an honorific prefixed to the given name. It derives from the Latin Dominus. In Portugal and Brazil, Dom (pronounced: [ˈdõ]) is used for certain hierarchs of the Roman Catholic Church and for laymen who belong to the royal and imperial families (for example the House of Aviz in Portugal and the House of Braganza in Portugal and Brazil). It was also accorded to members of families of the titled Portuguese nobility. Unless ennobling letters patent specifically authorised its use, Dom was not attributed to members of Portugal's untitled nobility: Since hereditary titles in Portugal descended according to primogeniture, the right to the style of Dom was the only apparent distinction between cadets of titled families and members of untitled noble families.