Space was designated backstage where actors could prepare for performances. By 1880, such spaces in newly constructed theatres were individual rooms for the leading players and larger common rooms for the supporting cast and chorus. Typically, the star dressing room was elaborately appointed. Most dressing rooms featured a dressing table, a mirror surrounded by lights to aid the actor in applying makeup, and a rack for costumes. A major innovation of the 1890s was fixed washstands in theatrical dressing rooms.
The Historical Dictionary of the American Theater. James Fisher.