noun (n)

• a person who participates in or is skilled at some game(noun.person)

  Synonym:
  participant
  

  source: wordnet30
• someone who plays a musical instrument (as a profession)(noun.person)

  Synonym:
  instrumentalist, musician
  

  source: wordnet30
• a theatrical performer(noun.person)

  Synonym:
  actor, histrion, role player, thespian
  

  source: wordnet30
• a person who pursues a number of different social and sexual partners simultaneously(noun.person)

  source: wordnet30
• an important participant (as in a business deal)(noun.person)

  Example:
  He was a major player in setting up the corporation.
  

  source: wordnet30
• One who plays, or amuses himself; one without serious aims; an idler; a trifler.(noun)

  source: webster1913