A gunnysack is a big, rough bag, usually of coarse cloth (often jute), used to hold heavy, dirty, or farmish things: grain, potatoes, coal, animal feed. The cloth is scratchy, brown or tan, and you can see the weave. People also write gunny sack as two words, and in some places they say hessian sack or burlap bag for the same kind of bag. It is a practical, slightly old-fashioned word — warehouses, farms, and old photos — not a school backpack and not a plastic supermarket bag. Because the cloth is cheap and strong, empty gunnysacks get reused, and children in some countries still jump in sack races with bags like these.