Blight is a "condition of property or the uses of property in parts of a city, town, or neighborhood that are detrimental to the physical, social, and/or economic well-being of a community. It can include abandoned buildings or those severely neglected by their owners, vacant lots full of rubble and garbage, or dangerous and/or illegal uses such as crack houses." [1]
See also: slums, Kelo v. New London A slum is an overcrowded and squalid district of a city or town usually inhabited by the very poor. ... Court membership Case opinions Laws applied U.S. Const. ...
References
UrbanPlan (Glossary)
Sacramento Transportation and Air Quality Collaborative (Glossary)
Frequently, however, urbanblight is used in specific reference to the properties of which a city is comprised and their abandonment.
Urbanblight is transmitted through vicious circles in which urban decay leads to social changes (in behavior, the economic base, etc.) which then result in further decay.
They may, however, make a valid contribution to efforts to redress urbanblight, and may have a particularly important role to play in encouraging community pride and the sense that other schemes to redress abandonment are being undertaken in conjunction with the efforts of local residents and not simply by autonomous and anonymous local authorities.