A listener named Korgan Rivera writes:
I’ve been listening to Grammar Girl for a long time, but … can’t recall this question being answered before. In sentences like “What’s wrong with you, you idiot?” or “You genius! You’ve solved it!” what is the word ‘you’ doing in these sentences? [in the You idiot! and You genius! parts]
This is a great question, and Korgan’s right: We haven’t answered it. For the rest of this episode, for the examples of this construction, I’m going to use the word wazzock, which is a British English word Ben Zimmer mentioned earlier this year in an episode of the Lexicon Valley podcast. In that episode, lexicographer Zimmer quotes an article from The Guardian, which says that wazzock is “one of a number of faintly limp insults that are more often used ironically than in serious,” and that it can “be used on the telly without frightening your gran.”
We need a word to refer to expressions like you wazzock. There isn’t a settled terminology for them yet, so I’m going to call them evaluative phrases. The question of what you is doing in these evaluative phrases is actually two questions:
First is the more specific question of what part of speech you is, and second is the more general question of exactly what kind of thing an evaluative phrase is. Is it a sentence, an interjection, or what?
‘You’ Is Usually a Pronoun
So let’s start with the part of speech for you. Even if you don’t know a lot about grammar, chances are good that you recognize you as a pronoun, more specifically a personal pronoun, just like I, me, he, him, she, her, them, and they. So it may surprise you to learn that according to some linguists, not only is you doing an unusual job in phrases like you wazzock,; it’s actually not even a pronoun! What?!
‘You’ Can Also Be a Determiner
What is it, then? Well, the Cambridge Grammar of the English Language argues that it’s in the same category as words such as the definite articles a and the, and words such as this, that, every, and some. Syntacticians call these words determiners. There are different categories of determiners; for example, the and a are articles, and this and that are demonstrative determiners. You is a personal determiner. The only other personal determiners in English are we and us, as in We snails have to stick together and Everybody loves us aardvarks.
If you’re a longtime listener, I know what you’re thinking right now. You’re thinking, “But Grammar Girl, in episode 288, you said that in compound nouns such as gumball, gum isn’t an adjective; it’s a noun that modifies another noun. So why can’t we just say that you, we, and us are pronouns that are acting like determiners?” This is a good point. On the other hand, in a sentence like Aardvark booked the flight, we don’t say that book is a noun that is acting like a verb; we say that it actually is a verb. So what’s the difference? Why can’t we just say that the you in you wazzock is still a pronoun, even though it happens to be doing the job of a determiner?