Ponyboy

In my opinion, the Greasers are properly defined when Ponyboy discusses their differences from the Socs.

Chapter One:

Greasers are almost like hoods; we steal things and drive old souped-up cars and hold up gas stations and have a gang fight once in a while. I don't mean I do things like that. Darry would kill me if I got into trouble with the police. Since Mom and Dad were killed in an auto wreck, the three of us get to stay together only as long as we behave. So Soda and I stay out of trouble as much as we can, and we're careful not to get caught when we can't. I only mean that most greasers do things like that, just like we wear our hair long and dress in blue jeans and T-shirts, or leave our shirttails out and wear leather jackets and tennis shoes or boots.