Plat

In the United States, a plat ( or ) (plan) is a cadastral map, drawn to scale, showing the divisions of a piece of land. United States General Land Office surveyors drafted township plats of Public Lands Surveys to show the distance and bearing between section corners, sometimes including topographic or vegetation information. City, town or village plats show subdivisions broken into blocks with streets and alleys. Further refinement often splits blocks into individual lots, usually for the purpose of selling the described lots; this has become known as subdivision.

After the filing of a plat, legal descriptions can refer to block and lot-numbers rather than portions of sections. In order for plats to become legally valid, a local governing body, such as a public works department, urban planning commission, zoning board, or another organ of the state must normally review and approve them. Provided by Wikipedia