oowop
An Uzi machine gun 

This term is mentioned often in early 90s New York rap songs.

"Pullin' out the oowop, listening to doowop"--Q-Tip, A Tribe Called Quest, "Everything Is Fair" 

"You get the Tec-9, I'll get the oowop"--Bad Mentalz, Trends of Culture, "Who Got My Back?"