The act of judging people by the labels of their clothes.
Here are a few examples of labelism:
1(in Abercrombie): I'm so classy.
2 (in Hollister): Me, too.
3 (in American Eagle): Don't forget me.
1: We all rock!
4 (in Aeropostale): Hey, I'm classy, too!
1: You wish, you wannabe!
2: Yeah, Loser!
5 (in Wal-Mart clothes): I'm pretty classy myself.
1: Eeeeeeeeew! Get away! You're poor!
2,3, and 4: Gross! White Trash! Nasty!
5: Whatever, you label whores!