Are Acis and Galatea by Handel, and Mussorgsky's Boris Godunov, both operatic works?
Acis and Galatea (Handel):  The work has been variously described as a serenata, a masque, a pastoral or pastoral opera, a "little opera" (in a letter by the composer while it was being written), an entertainment and in the New Grove Dictionary of Music an oratorio. Boris Godunov (opera): Boris Godunov (Russian: Борис Годунов , "Borís Godunóv") is an opera by Modest Mussorgsky (1839–1881). Boris Godunov (opera):  It is Mussorgsky's only completed opera and is considered his masterpiece.
yes