1. Used to describe a person that is beyond being a simple dickhead.
2. A pompous, arrogant son of a bitch, who is so full of themselves that they make the average Joe Dickhead appear acceptable.
3. The nastiest and meanest of all dickheads.
Co-worker #1: Geez, our new boss is a helluva dickhead.
Co-worker #2: True, but he isn't as bad as that dickhead and a half we had before him.