You can use models to document existing databases in Talend Cloud Data Catalog.
Talend Cloud Data Catalog has a business glossary application that allows you to manage terminology and domain definitions across the enterprise. You can reuse these definitions not only among different enterprise applications and between versions of the same application. You can use a glossary to collect and apply naming standards based upon the name assignments made when editing a model.
In addition, Talend Cloud Data Catalog allows you to link tables and columns to terms and glossary domains and business rules.