While I'm at it, I should add that neologisms also enter the language every time a new genre of music develops.  The OED includes relatively new entries for heavy metal, thrash, acid jazz, Afrobeat, and so many others.  As long as there is new music there will always be new words.

Music is also a source for cross-pollination between languages.  English has many loan words from Italian (opera, aria, forte, piano, etc.) due to Italy's enormous contributions to musical culture in the past.  Likewise we can find 'pop' and 'rock' in use in dozens of languages around the world today.