A "slab" is a flat, thick piece of material, often made of concrete, stone, or metal. It is commonly used in construction for floors, roofs, and foundations. Slabs provide a stable surface and are essential for building structures like houses and bridges. In geology, a slab can refer to a tectonic plate that sinks into the Earth's mantle at a subduction zone. This process can lead to geological events such as earthquakes and volcanic eruptions. Understanding slabs in both construction and geology is important for safety and structural integrity in various applications.