noun (n)

• one who precedes you in time (as in holding a position or office)(noun.person)

  source: wordnet30
• something that precedes and indicates the approach of something or someone(noun.communication)

  Synonym:
  forerunner, harbinger, herald, precursor
  

  source: wordnet30
• One who precedes; one who has preceded another in any state, position, office, etc.; one whom another follows or comes after, in any office or position.(noun)

  source: webster1913