One silly argument I had was with a friend while on a bus trip to Canada that had movies playing on it.
One of the movies in the cue was
Evita (1996). My friend described it to me as being almost totally done with song.
I said, "so it's an opera."
He said no, it wasn't an opera, but it was all done with song.
I said, well that's an opera.
He said it wasn't opera music and I replied that although there is a style of music people consider as classical opera, that the word can still describe any story told entirely with music and I cited
Jesus Christ Superstar as a "Rock Opera."
He said that was different since
Jesus Christ Superstar was a "
Rock Opera."
I said it's still an opera, but it uses rock-style music thus they called it a "Rock Opera."
So he says Evita is not a rock opera or any kind of an opera because it's not opera music.
I said we just clarified that any type of music can be used and it can still be an opera - so if it's done almost entirely with song telling the story, no matter the style of music used, then it's an opera.
He said, "It's not an opera."
I have to admit I never did see it as we reached our destination before the movie could play, so I don't know if it was just a musical (music mixed with dialogue) and his description was incorrect that almost the entire thing was done in song or if it could actually fit the definition of an opera.