Whatever those kids across the ocean(america) are playing. Another term used to describe the so called "american football" which any sensible person would agree that name is shit. Kind of like rugby but players have to wear padding and armour and look like they're fighting a war on the pitch hence the name armoured rugby.
American 1: did you catch the game of football yesterday?
Brit 1: football? Which league?
American 1: the super bowl?
Brit 1: ohh you mean the armoured rugby game