https://doc.esri.com/en/arcgis-pro/latest/help/mapping/properties/coordinate-systems-and-projections.html

A local coordinate system uses a false origin (0, 0 or other values) in an arbitrary location anywhere on earth. Local coordinate systems are often used for large-scale (small area) mapping. The false origin may or may not be aligned to a known real-world coordinate, but for the purpose of data capture, bearings and distances can be measured using the local coordinate system rather than global coordinates. Local coordinate systems are usually expressed in meters or feet.

Example:

https://slcprdpublicrecords.blob.core.windows.net/0001sjradmin/PDF/CB_1877_15_10045793.pdf