V- To masturbate, often with the aid of porn or in a circle of people masting. Usually accompanied with an "aww yehh!"
V- To ejaculate.
N- A single act of masturbation.
1- My friend and I like to watch each other mast and go "aww yeah!"
2- I masted all over her face last night.
3- I think I'm gonna get a mast in before class.