Chinese Submarine
(noun) an alcoholic beverage concealed within a larger receptacle that prevents the rousing of suspicion when in public areas that prohibit the use of such substances.
Guy 1 "I'd love to see that movie tonight, but I really wanna drink."
Guy 2 "No problem. Just grab a large cup from the snack stand and make a Chinese Submarine."
Guy 2 "No problem. Just grab a large cup from the snack stand and make a Chinese Submarine."