Antecedent, forebear (8)
I believe the answer is:
ancestor
I believe this clue is a double definition.
'antecedent' is the first definition.
(synonyms)
'forebear' is the second definition.
(a forebear is an ancestor or predecessor)
(Other definitions for ancestor that I've seen before include "not being of the modern generation" , "Forefather" , "Old member of the family -no traces (anag)" , "One of one's forebears" , "Person from whom one is descended" .)