A bread bowl is a round loaf of bread which has had a large portion of the middle cut out to create an edible bowl. They are typically larger than a roll but smaller than a full sized loaf of bread.
Bread bowls can be used to serve chili, New England-style clam chowder, and other thick stews (often, but not always, with a cheese or cream base). Soups with thinner bases are not generally served in bread bowls, as the broth would make the bread get too soggy too quickly. The bread becomes flavored as it absorbs some of the stew's base, and can be eaten after the stew has been eaten. Bread bowls are also used for dips, using the scooped-out bread for dipping.
One of the traditional recipes that uses a bread bowl is Knorr Spinach dip made with their vegetable mix package. This classic recipe in a bread bowl is make with a round pumpernickel bread loaf.