The buildingSMART Data Dictionary (bSDD)

The buildingSMART Data Dictionary (bSDD) is an online service that hosts classifications and their properties, allowed values, units and translations. The bSDD allows linking between all the content inside the database. It provides a standardized workflow to improve data quality and information consistency. The most important part of the bSDD are the APIs, Application Programming Interfaces, accessible via the internet. Using those APIs other tools and systems can use the data stored in the bSDD.

More info on https://www.buildingsmart.org/users/services/buildingsmart-data-dictionary/

Documentation

Find the documentation here