Bitch/Jerk
From Super-wiki
When younger, Sam and Dean had a ritual where Dean calls Sam a "Bitch" and Sam responds with "Jerk".
While this is strongly associated with the characters, it has only been referenced three times on the show:
Watch a video compilation of references here.
In 10.01 Black, the exchange occurs between Crowley and Dean, signifying his demonic lack of care for Sam and his newfound relationship with [{Crowley]].
See also: Nicknames