Being a douchebag by pretending you know more than you really do. Wnen someone is Nicking it up, the people around him usually notice, and then converse about it later
Me: Dude, remebr that time in the Bahamas when _______ was Drunk.
Me: Dude you weren't there.
Nick: Oh Yeah
Me: you're a Douchenozzle.
Everyone Afterwards: He was Really Nicking it up.