Dictionary entry

Progenitor

Webster's Dictionary 1913

Pro‐gen″i‐tor (?), n. [OF. progeniteur, L. progenitor, fr. progignere, progenitum, to bring forth, to beget; pro forth + gignere to beget. See Gender kind.] An ancestor in the direct line; a forefather.

And reverence thee their great progenitor. Milton.