player

Noun

• an important participant (as in a business deal)
  • he was a major player in setting up the corporation
    

• a person who pursues a number of different social and sexual partners simultaneously

• a theatrical performer

• someone who plays a musical instrument (as a profession)

• a person who participates in or is skilled at some game

Related words

• Synonyms: 
  actor , histrion , thespian , role player , musician , instrumentalist , participant