The act of failing to take any responsibility for your own loses, failures or shortcomings, and blaming them on anyone other than yourself. Usually used in context of video games, but can also apply to real life.
Someone who is 'newting' can also be referred to as a 'newt'.
Newt: "It's not my fault I lost, that guy was using an overpowered character!"
Guy: "Stop newting and just accept that you're bad"
Named after Georgian Congressman Newt Gingrich who visited his first wife in hospital (she was recovering from surgery) to discuss the terms of their divorce. Also, he was cheating on her.
Guy1: Dude, my wife is really sick.
Guy2: Oh, really? Wow... what are you going to do?
Guy1: I'm thinking about Newting her.
Guy2: Oh.