The concept of rap as street poetry has been with the genre from the very beginning. Spoken-word artists like Gil Scott-Heron and the Last Poets collective were foundational influences on early rappers. KRS One's lead track on 1987's Criminal Minded was called, simply, "Poetry." In 1999 Nas announced, "I'm a poor man's dream, a thug poet," and in 2001 Eminem labeled himself a "modern-day Shakespeare"—a claim the director of the Royal Shakespeare Company backed up a decade later. In recent years the rap-poetry link has only been reinforced by scholarly anthologies, published lyrics collections like Jay-Z's Decoded, and of course, Rap Genius.

But do today's rappers still call themselves poets? Increasingly, according to RG's new RapStats feature, the answer is no:
The above chart tracks mentions of "poet" and "poetry" in hip-hop lyrics over the past 25 years. As you can see, they've nosedived since the '90s. So has "verse," surprisingly enough. And who'd have guessed that rappers have rhymed less about "rhyme" over time?
You might assume that this is because rap has outgrown a self-conscious early phase in which it was still defining itself as a genre. And in part that's probably true. (Names like "Busta Rhymes" are now antiques, relics from the days when the whole form had to be explained to mainstream audiences: "Rap is where you rhyme over a beat…") Still, "rhyme" and "verse" aren't rap-exclusive terms; they're used in written poetry also. Compare a term like "flow," which is more particular to hip-hop:
This one's held up pretty well. It could be that the word "flow" is just more versatile than the others (thoughts and rivers can "flow," too), as well as more useful within the art form, since it covers the complex interactions between words and rhythm. But it could also be that rap has, consciously or unconsciously, defined itself apart from the world that calls itself "poetry." Maybe these trends are a visual index of what fans already know: rap has become an art on its own terms, with its own terms of art.

In any case, there are a few words that buck the trend. Although nowhere near as common as "flow" or even "rhyme," "allusion" surfaced in rap for the first time in 2009 and has appeared a handful of times in each year since. ("Reference" has had an even better run.) And check out "onomatopoeia"—it's practically a fad, with Lupe Fiasco, André 3000, and Bun B, among others, all dropping it in the past few years.
So much for labels and jargon. RapStats also offers insights into deeper questions, such as how hip-hop artists engage with traditional poetic subjects. Here's the chart for "truth" and "beauty":
In rap, the two are not equal. (Or if they are, the one term is definitely preferred.) It's no surprise that this raw, bullshit-calling genre privileges the first over the second—but it's kind of nice to see "beauty" gaining ground. And behold the "sublime"…
How about that most Romantic of subjects, "imagination"?
You heard it here first: rappers aren't keeping it as real as they used to. ("Reality" has declined over the same period, but it's still got the edge for now.)

Between the "human" and the "divine," rap seems to come down firmly in favor of the human.
But wait: what about "man" and "God"?
Convergence! Either rappers are becoming more spiritual, or more of them are adopting Kanye's private theology: "I Am a God."

Critics who view rap as fundamentally angry, bitter, cynical, etc. may be surprised to find that the lyrics tell a different tale: it really is all about the love. "Love" triumphs easily over "hate," and "hope" beats "despair" in a landslide.

In fact, "hope" has been on a virtually unbroken 25-year upswing. Interestingly, though, "despair" peaks right around the time the economy tanked in 2008.
So does "injustice":
Then there's the question of aesthetics. Hip-hop, like Pac, "grew from concrete." Again, it's in love with the gritty, the raw, the real. In a battle between "abstract" and "concrete," you'd expect the concrete to whoop ass.
Instead there's only a moderate gap—and both words have fallen in popularity. What's really interesting, though, is how closely the shapes of the two graphs resemble each other. It seems these terms are actually correlated, suggesting that a surprising number of rappers are using "concrete" metaphorically (to mean "the opposite of abstract") rather than literally ("the stuff pavements are made of"). Or else using it in both senses at once, as part of a pun.

Finally we come to the biggest subject of them all.
Tragically, “death” peaks in 1996-97, at the height of the East Coast/West Coast feud that killed 2Pac and Biggie. But "life"? Life peaks now. And if you agree with Gwendolyn Brooks that poetry is "life distilled," that means hip-hop, all labels aside, has never been more poetic.