Originating at the RC(Air)C summer course Survival Instructor Course, (6 week course) a Teamsmash is when a large group of Survival Instructors shit in one blue rocket (portapotty) on the day they are leaving on the bus after graduation day
F Sgt: Sgt you gotta totally teamsmash on your last day of SI this summer, carry on the tradition for me.
Sgt: that's disgusting but alright
Army Course cadet enters a teamsmashed portapotty
army course cadet: you guys are fuckin nasty man!
SI's laugh their asses off