progenitor
I
noun
ancestor, antecedent, antecessor, begettor, forebear, forefather, foregoer, forerunner, genitor, origin, parens, parent, precursor, predecessor, primogenitor, procreator, sire, source
II
index
ancestor, ascendant, derivation, forerunner, parents, predecessor
Burton's Legal Thesaurus.
William C. Burton.
2006