1. A distinct, usually rectangular, section of the surface of a door, cabinet, wall, ceiling or roof. 2. A board containing instruments, controls, dials, and switches. 3. A group of people, usually three, forming an arbitration tribunal. 4. A large, thin board or sheet of lumber, plywood or other material. 5. A thin board with all its edges inserted in a groove of a surrounding frame of thick material. 6. A section of floor, wall, ceiling or roof, usually prefabricated and of large size, handled as a single unit in the operations of assembly and erection. 7. Form section consisting of sheathing and stiffeners that can be erected and stripped as a unit. 8. A recessed section on the broad face of a brick; see Frog.