post exchange 
noun
A shop at a US military camp, selling food, clothing, and other items.The post exchange at Camp Victory did not save a soldier who was killed by a mortar right outside its front door....
- While the soldiers lack a post exchange in which to shop, have limited laundry facilities and as of yet, no plane tickets home, they seem pleased with their temporary home.
- We stand in line to eat, shower, use the latrine and shop at the post exchange.