antenatus
noun
an·te·na·tus
plural antenati
-āˌtī
: a person born before a certain time or event especially with reference to the existence of political rights (as a person born in an American colony before the Declaration of Independence) —usually used in plural
eligibility of antenati to hold office
—opposed to postnatus 
Word History
Etymology
Medieval Latin, firstborn son, ancestor, predecessor, from Latin ante- + natus, past participle of nasci to be born
First Known Use
1653, in the meaning defined above