When someone falls victim to a DN joke, making them look like a fool while to person who made the joke will then be in the victims head rent free. Usually happens in a video game chat.
"'Do you know dragon?' 'No, who is dragon?' 'Dragon deez nuts across your face! Wow you just got zepped hard bro.'"
A person who has undergone decompression surgery to relieve pressure on the brain stem and to allow the cerebral spinal fluid to flow properly. Ususally as a result of trama or a condition known as Arnold Chiari Malformation in which the brain can become herniated down the spinal cord. The resulting scar looks like a zipper up the back of the head.