A popular word used by people with colorful and inside humor. "McFucking" does not have anything to do with McDonald's, It's simply a cute way of saying "fucking".
The act of physically diving into your pile of chips when you're winning at poker. Extra points if you break the card table and bring the game to a halt. Based on wealthy avian industrialist Scrooge McDuck's habit of diving into his vault of gold coins.
A: "How did the Texas Hold'em tourney go last night?"
B: "Wesley was getting tired of taking all of our money, so he ended up McDucking. He wouldn't even pay for a new table afterwards."