noun (n)

• the actions and activities assigned to or required or expected of a person or group(noun.act)

  Example:
  Play its role.
  

  Synonym:
  function, office, part
  

  source: wordnet30
• an actor's portrayal of someone in a play(noun.cognition)

  Synonym:
  character, part, persona, theatrical role
  

  source: wordnet30
• what something is used for(noun.attribute)

  Synonym:
  function, purpose, use
  

  source: wordnet30
• normal or customary activity of a person in a particular social setting(noun.act)

  Example:
  What is your role on the team?.
  

  source: wordnet30