Short for Polo. Back in the day, Lo-Lifes, Ralphies' Kids, and Polo USA (United Shoplifters Association) would run into stores in NYC and rack madd Lo gear. This is a purely New York City phenomenon.
Also: Kanye West may seem like a Lo head, but he's not. He's a new jack to the game.
Suicide Ski, 92 Ski, P-wing, Indian Head, etc.