Cities designed on an urban plan having a series of functionally specialized parallel sectors, such as a zone for railways, a zone for educational and cultural institutions, a residential zone, a park zone, an agricultural zone, and a green zone buffering the city from the highway. Such cities were ideally placed parallel to a river and so that winds would blow industrial air away from residential areas. The idea was developed by Arturo Soria for Madrid, Spain in the 19th century; other experiments took place primarily in Russia and Germany.

Source: AAT

http://vocab.getty.edu/page/aat/300008356