Basement

A basement is any floor level of a building that is largely or completely beneath the ground. Especially in residential buildings, it often is used as a utility space for a building, where items such as the furnace, water heater, breaker panel or fuse box, car park, and air-conditioning system are located; so also are amenities such as the electrical system and cable television distribution point. In cities with high property prices, such as London, basements are often fitted out to a high standard and used as living space.

In British English, the word basement is usually used for underground floors of, for example, department stores. The word is usually used with buildings when the space below the ground floor is habitable and with (usually) its own access. The word cellar applies to the whole underground level or to any large underground room. A subcellar or subbasement is a level that lies below the basement or cellar.