The act of pouring out some your alcoholic beverage for the gods. Used during the Classical period of Rome and Greece. Its basis is in the fact that there is a certain amount of alcohol you were going to drink in the given night, and you are sharing it with gods because you are not selfish.
A guy approaches another guy in a bar. "For the gods?", and as they each pour some of their drinks out, they other replies "For the Gods".