Actor \Ac"tor\, n. [L. actor, fr. agere to act.]

1. One who acts, or takes part in any affair; a doer.

2. A theatrical performer; a stageplayer.

After a well graced actor leaves the stage. --Shak.

3. (Law)
   (a) An advocate or proctor in civil courts or causes. --Jacobs.
   (b) One who institutes a suit; plaintiff or complainant.

Source: Webster's Revised Unabridged Dictionary (1913)