noun (n)

• someone from whom you are descended (but usually more remote than a grandparent)(noun.person)

  Synonym:
  antecedent, ascendant, ascendent, root
  Antonym:
  descendant, descendent
  

  source: wordnet30
• One from whom a person is descended, whether on the father's or mother's side, at any distance of time; a progenitor; a fore father.(noun)

  source: webster1913