Thirst : noun Sensation corresponding to the body's need for water.
It is thirsty! : hot weather that thirsts.
He is thirsty: The need to drink is felt. It's thirsty, come have a drink with meUntil more thirsty: excessively, extremely, until the end.
quotes from Jean carmet of the French actor (1920-1994): “You see when I've been drinking, but you don't see when I'm thirsty, do you think that's normal? Not me… ".