After splitting the g, when drinking a Guinness, you consequently finish the whole pint with one gulp. Meaning you drank a whole pint in 2 large gulps.
A phrase, primarily used by black men, used to describe the love of a friend's new haircut, usually followed by a slap to the neck/back of the head. It was originally used in a video of a kid playing Minecraft, followed by a man saying, "Ohh you playin' Minecraft?" and then slapping the back of the kids head.