A gazetteer is a directory of geographic identifiers describing location instances. It will contain
additional information regarding the position of each location instance. It may include a coordinate
reference, but it may also be purely descriptive. If it contains a coordinate reference, this will enable
transformation from the spatial reference system using geographic identifiers to the coordinate
reference system. If it contains a descriptive reference, this will be a spatial reference using a different
spatial reference system with geographic identifiers, for example the postcode of a property. For any
location type, there may be more than one gazetteer