What do we mean when we sing "O"?

What's the most common word used in vocal music? If you're into opera, I suppose "love" (or "amore", "amour" or "lieb") would be the logical guess.

But I'll bet you a shiny dime that "love" doesn't even approach the instances of the simple word "oh". This word is everywhere!

England's "own goal". Oh no!

Oh! Susanna, do not cry for me
("Oh! Susanna", by Stephen Collins Foster)

O dolce fanciulla
(Rodolfo in Act 1 of Puccini's La bohème)

Oh, the pops are sweeter and the taste is new/They're shot with sugar through and through.
(Vintage advertising jingle for breakfast cereal, ca. 1960's)

O du mein holder Abendstern
(Wolfram's aria in Act III of Wagner's Tannhauser)

It's the shortest word in any opera libretto, song, or TV jingle. It's found in all languages. But why does it exist? What does it add that we would miss if it wasn't there? 

Language - so interesting; so weird.

Meaning in language always depends on context. "O" sometimes means "Hey", as in "hey you!"; in other words, as an implied manner of catching someone's attention. Faithful Blog Readers of a certain age may remember radio commercials for the Culligan water treatment company. Every commercial ended with a female voice yelling (in a Long Island-ish accent): "Oh, CULLIGAN MAN!", as if the dude was driving away and she was trying to flag him down. 

Perhaps that's what Rodrigo had in mind as he dies in Verdi's Don Carlo when he gasps "O Carlo, ascolta" (Oh Carlo, listen.) Put yourself in his place. You've been mortally wounded; you know you'll be dead in a few moments and you have something important to express to your BFF Carlo before you go. If you simply say "Carlo, ascolta", without the "O", he might not be listening; he might be so upset to see you in this condition that he's not focused on what you are saying. So that "O" is the equivalent of today's ubiquitous "YO!" 

But then again, maybe he is expressing more than that. In addition to the "hey you" implication, isn't that "O" also laden with despair and desperation? Isn't it a groan of regret? I imagine that millions of British soccer fans (pardon me; of course I meant "football fans") were moaning "Ohhhhhhhhhhhh" when England's Laura Basset kicked the ball into her own goal, dooming her team to lose to Japan in the semi-finals of the Women's World Cup a few weeks ago. Yeah, "O" can be that sort of emotional exhalation as well. As I write this, I'm watching the third round of golf's British Open on TV; one of the leaders sliced his tee shot so badly it struck the roof of a building abutting the course. This prompted the commentator to exclaim "Ohhhhh nooooo" in shocked disbelief. "Oh" can be a reflexive utterance, like "Ow" when you stub your toe.

It's a versatile word. It's also a linguistic stalling device; a way of giving yourself time to think through the thing you're about to say. If someone asks "What do you want for lunch?", you might well respond :Ohhhhh, I don't know. Soup, I guess." That's also the role played by "um", "well", and their annoying cousin "y'know". But is there an opera aria that puts "oh" to that use? I can't really find one.

"Oh" can also be the response to information received; a way of saying. "I see"; an acknowledgement of another's statement:
"I just read where another state legalized same-sex marriage."
"Oh."
That usage isn't really a good fit with opera, as it's characterized by the absence of emotional affect, rendering it pretty much anti-operatic.

Of course, not all emotional outbursts are tragic as that of Verdi's Rodrigo or those British soccer fans. "O" can also be a sigh of pleasure or happy surprise. A good example is Vasco de Gama's aria in Act IV of Meyerbeer's L'Africaine, "O Paradis", which could be updated to "Dude! This is, like, paradise!" 

Sometimes the context of an "O" suggests acknowledgement of due respect; a certain formality of address. I'm thinking here of the Rev. Olin Blitch's prayer "Hear me, O Lord" in Floyd's Susannah and Sarastro's "O Isis und Osiris" in The Magic Flute. When summoning deities, it's good form to be highly awestruck and respectful.

So here's a game you can play the next time you're at the opera: look for instances of our new favorite word "oh" and do a bit of quick analysis. What the character expressing with that "oh", and how would the sentence be changed if it wasn't there?

Um, I never said it would be your favoritei game...

What's that? You think you're unlikely to do that?

Oh.