Finger Bang is the name of the boy band the boys from
South Park and Wendy try to start up in order to make Cartmen's life
long dream come true, to make ten million dollars.
To finger bang to use ones finger as a
gun.
Finger Bang to rapidly insert one's finger(s) in and out of the pussy or anus.
"Have you heard Finger Bang's new cd? It's
banging!"
With the hand in a
gun shape - "Bang Bang I shot you down."
Guy 1 "So how was having Anna over last night?"
Guy 2 "Oh it was totally great I finger banged her all night
long."