primogenˈital, primogenˈitary and primogenˈitive adjective

primogenˈitive noun (Shakespeare)

Primogeniture

primogenˈitor noun

1. An earliest ancestor
2. A forefather
3. The founding ancestor of a people

primogenˈitrix noun

A female ancestor

primogenˈiture noun

1. The circumstance of being first-born
2. The principle or right of inheritance of the first-born child or (male primogeniture) son

primogenˈitureship noun (rare)