A non-existant ten pound note, which is used for the purpose of online wagers or bets with others; where there is no intention of money changing hands regardless of the outcome.
The phrase originates from the online UK motorbike forum 'Visordown', specifically a user called 'Soapy' known for making bets with no intention paying anything.
The act of inserting an open bottle of whiskey into the anus of a person doing a handstand. The person then rights themself while people take shots out of the now whiskey flowing butthole.
Man, I was so wasted from all those Tennessee back door's last night ... Do I still have shit in my teeth?