A cesspit, or cesspool, is a term with various meanings: it is either used to describe an underground holding tank (sealed at the bottom) or a soak pit (not sealed at the bottom). It can be used for the temporary collection and storage of feces, excreta or fecal sludge as part of an on-site sanitation system and has some similarities with septic tanks or with soak pits. Traditionally, it was a deep cylindrical chamber dug into the earth, having approximate dimensions of 1 metre diameter and 2–3 metres depth. Their appearance was similar to that of a hand-dug water well.

The pit can be lined with bricks or concrete, covered with a slab and needs to be emptied frequently when it is used like an underground holding tank. In other cases (if soil and groundwater conditions allow) it is not constructed watertight allowing liquid to leach out (similar to a pit latrine or to a soak pit). (source)