Circumvallate refers to a specific arrangement of structures or features that are surrounded by a wall or barrier. In a geographical context, it can describe a fortified area or a military encampment that is enclosed by a defensive wall. This term is often used in archaeology and history to discuss ancient fortifications. In the context of anatomy, circumvallate can refer to the circumvallate papillae, which are large, dome-shaped structures located on the back of the tongue. These papillae contain taste buds and play a role in the sense of taste, particularly in detecting bitter flavors.