void A hole in a rock. If they are interconnected, voids form paths along which water and other fluids may flow. In increasing order of size, the major types of voids are: intercrystalline boundaries; intergranular pores or spaces between the grains of a sediment; microfractures or local cracks, usually extending for only a few tens of centimetres and from a few micrometres to 0.1 mm wide; fractures including joints, small faults, and bedding planes, which are often extensive and may have openings up to a few millimetres wide; fissures formed by solution, weathering, or local gravitational or tectonic displacement, and up to about 10 cm wide; and solution channels, which range up to several metres wide and many hundreds of metres long.

Void (in Buddhism): see ŚŪNYATĀ.