I ran across an analysis done on 99 musicians across 25 different genres that sought to discover the artists with the largest vocabularies—that is, the number of unique words that have appeared in their lyrics over the years.
Hip hop artists came out on top—which is not surprising, considering the lyrical density of their songs. The current vocabulary champion is Eminem with 8,818 words, followed by Tupac and Jay Z, both in the 6,500 range. The rocker with the biggest vocabulary is Bob Dylan with about 4,900. And the alt-rock act with the most words in their songs is the Red Hot Chili Peppers. When this analysis took place, Anthony Kiedis had used 3,636 distinct words in Chili Pepper songs. And just for fun, where was Nirvana? Number 83 with 1,835 words, less than Mariah Carey, Britney Spears and Katy Perry.