A term used to describe the stage, scene or act of an opera. Also, a term for a set of vocal movements in a theatrical production, usually including a recitative, arioso, and aria.also describes an episode in opera that has no formal construction, and is usually made up of arias, recitative and other elements. It may be an extended dramatic passage-often involving a single character-such as the sleepwalking scene in Verdi's Macbeth