Toping, Short for Isotoping, is the act of illegally enriching uranium, often with the goal of selling it to terrorist countries. It is becoming a teen craze, comparable to drug use, with students bragging to each other about how much nuclear material they "toped" the night before.
Person 1: Hey, you coming to Mike's Toping party tonight?
Person 2: Yeah, it's gonna be awesome - You got any safety goggles? I left mine at Sam's house last week.