A chitter is a wooden box with 2 compartments which hold a one hitter. The large compartment is for storing the pot (Fits about an eighth) and the smaller compartment stores a one hitter or a "bat." They are very discrete and due to the small amount loaded into the chitter, there's very little waste of grass.
Dude A: I ran out of weed, do you have anything in your chitter?
Dude B: Nah, I smoked everything that was in my chitter box when I woke up this morning.