Wikipedia has an article on: ultimogeniture Wikipedia ultimogeniture (countable and uncountable, plural ultimogenitures) A system of inheritance in which...
borough English (uncountable) (law, UK, obsolete) Patrilineal ultimogeniture; inheritance by the youngest surviving male child. Synonym: junior right 1765–1769...
of a privileged position in, a parent’s wealth, estate, or office; ultimogeniture. 1865, “Revue Historique de droit Français et Étranger”, in The Journal...
in their origin. (antonym(s) of “inheritance by first-born child”): ultimogeniture, postremogeniture absolute primogeniture agnatic primogeniture matrilineal...