Now, it might be easy to think that this "up" is just "slang." But what kind of slang lives on, decade after decade? It won't do to object that this "up" doesn't make literal sense, because other ways that we all use "up" are similarly nonsensical. In what sense is making up with someone vertical (when in certain cases it distinctly isn't!)? If someone is all washed up, what is that person above, and in what way is someone successful if he or she is more horizontal?

And if "up" is slang, then why, in other languages, when there is a similar way of conveying that same kind of meaning of intimate proximity, it's treated as grammar? In Korean, "put" is a different word depending on how intimate the puttage is. You nohta a cup on the table, nehta an apple into a bowl and kkita a videocassette into its box. It's a lot like the Ebonics "up": In a way, you slide that videocassette all "up" into the box.

The "intimate up" is one of several ways that Black English is complicated, and in a way that even Standard English isn't. A foreigner, if assigned to learn English in South Central instead of a classroom, would have trouble mastering how to use "up" in this way. One imagines him telling a child something like "OK, get nice and up into bed" -- but no, that's not quite right. It is, in a word, incorrect Ebonics. Black English is, despite its humble and even randy associations, a grammar, a system -- and a challenging one to make sense of, at that.

And "up" is just the beginning -- stay tuned for another one in May.

John McWhorter is a regular contributor to The Root.

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