See predecessor in Webster's New World Roget's A-Z Thesaurus II
noun
One that precedes, as in time:
ancestor, antecedent, forerunner, precursor, progenitor. See precede- (Archaic)
A person from whom one is descended:
ancestor, antecedent, ascendant, father, forebear, forefather, foremother, mother, parent, progenitor. See kin, precede
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