Geographic name holds the proper noun of certain objects within the Topo databases. Geographic_name does not apply to roads, railway lines, or descriptive text - eg 'Brunner Mine' would be a Geographic_name but 'mine disused' is held in the descriptive_text feature
Data Dictionary for geographic_name: https://docs.topo.linz.govt.nz/data-dictionary/tdd-class-geographic_name.html
This layer is a component of the Topo500 data. The Topo500 map series will, when it is created, provide updated topographic mapping for the New Zealand mainland at 1:500,000 scale.