Tronning

Tronning is the act of walking beside someone then suddenly moving in front of them and stopping. This word also applies to walking in front of someone and slowing down, or any related situations between vehicles. This is a reference to the video game/movie Tron in which light bikes aim to cut in front of each other to destroy one another.

*Ashton and Jimmy are walking to class, and Jimmy suddenly cuts in front of Ashton and stops. Ashton, having not seen the encounter coming, walks into Jimmy.*
Ashton: Dude, stop tronning me!