A person who acts a part in a theatrical play or (later) in film or television; a dramatic performer.
Someone or something that takes part in some action; a doer, an agent.
The entity that performs a role (in use case analysis).
The subject performing the action of a verb.
A creative artist, especially a film director, seen as having a specific, recognisable artistic vision, and who is seen as the single or preeminent ‘author’ of his works.