Importing OSM user-maintained special phrases
As described in the Import section, it is possible to import special phrases from the wiki with the following command:
nominatim special-phrases --import-from-wiki
Importing custom special phrases
But, it is also possible to import some phrases from a csv file. To do so, you have access to the following command:
nominatim special-phrases --import-from-csv <csv file>
Note that the two previous import commands will update the phrases from your database. This means that if you import some phrases from a csv file, only the phrases present in the csv file will be kept into the database. All other phrases will be removed.
If you want to only add new phrases and not update the other ones you can add
--no-replace to the import command. For example:
nominatim special-phrases --import-from-csv <csv file> --no-replace
This will add the phrases present in the csv file into the database without removing the other ones.