A tenement is, in most English-speaking areas, a substandard multi-family dwelling in the urban core, usually old and occupied by the poor. (In Scotland it still has its original meaning of a multi-occupancy building of any sort, and in parts of England, especially Devon and Cornwall, it refers to an outshot, or additional projecting part at the back of a terraced house, normally with its own roof.)
Read more about Tenement: History