1) Actively thinking (e.g. doing homework) while enjoying an alcoholic beverage(s).
Most notably used in reference to "think and drink thursday"
Steve: Yo man its been a rough week, I dunno how I am gonna be able to get through all my homework tonight.
Randy: Not to worry steve, tonight is think and drink
thursday. Ill pick up a case of the high life and we will get our shit done.