Is it an opera or a musical? Anthony Tommasini offers a distinction that might settle the argument discussion that Leta and I regularly have:
Both genres seek to combine words and music in dynamic, felicitous and, to invoke that all-purpose term, artistic ways. But in opera, music is the driving force; in musical theater, words come first.
This explains why for centuries opera-goers have revered works written in languages they do not speak. Though supertitles have revolutionized the art form, many buffs grew up without this innovation and loved opera anyway.