a genre of music that's not just Nirvana and Pearl Jam. Mainly consists of dirty guitar chords with lower tuning and lots of distortion. The grunge "look" consists of ripped jeans, flannel shirts and a I-don't-care attitude. The so called "godfather" of grunge, Kurt Cobain hated the word to describe the music. Nirvana was the first to popularize grunge (unintentionally), but they are not the only grunge band, Alice in Chains and Soungarden are other examples. If you want to act grunge, you have to be chilled out and not really care, respect women and others and hate jocks. Obscure indie bands are good too.
Grunge isn't dead, it's just taking a lazy afternoon nap.