grand opera 
noun
1An opera on a serious theme in which the entire libretto (including dialogue) is sung.The rest of the set is full of party pieces with exhilarating recordings of the Bizet suites, overtures by Hérold, Auber, Thomas and the obligatory ballet music by Gounod and Berlioz from the grand operas....
- The opera laid the historical groundwork for Boris Godunov, Khovanshchina and a host of ensuing historically-based Russian grand operas.
- Although Der Cid has elements in common with Lohengrin, it can stand independently as one of the most remarkable German grand operas of the day.
1.1 [mass noun] The genre of grand opera.Dvoák stayed with the theatre orchestra until the summer of 1871, acquiring a solid knowledge of French grand opera, operetta, Verdi, and Mozart....
- Other notable masters of 19th century bel-canto and grand opera are Bellini, Meyerbeer, Weber, Gounod and Massenet.
- Grand opera - even Wagnerian grand opera - deals in large, as opposed to detailed, meanings.