primogenitor

[ prahy-muh-jen-i-ter ]
/ ˌpraɪ məˈdʒɛn ɪ tər /

noun

a first parent or earliest ancestor: Adam and Eve are the primogenitors of the human race.
a forefather or ancestor.

Origin of primogenitor

1645–55; < Late Latin prīmōgenitor ancestor, equivalent to Latin prīmō at first + genitor genitor
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

British Dictionary definitions for primogenitor

primogenitor

/ (ˌpraɪməʊˈdʒɛnɪtə) /

noun

a forefather; ancestor
an earliest parent or ancestor, as of a race

Word Origin for primogenitor

C17: alteration of progenitor after primogeniture
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012