Curtain call the appearance of one or more performers on stage after a performance to acknowledge the audience's applause.
curtain lecture an instance of a wife reprimanding her husband in private (recorded from the mid 17th century, and originally a reprimand given behind bed curtains).
curtain-raiser an entertainment or other event happening just before a longer or more important one (recorded from the mid 19th century, and originally used in the theatre to denote a short opening piece performed before a play).
curtain wall a fortified wall around a medieval castle, typically one linking towers together.
See also bamboo curtain, iron curtain.