DBMS is a far more common acronym for database management system than DMS.
The Wikipedia page for database management systems does not mention this acronym. A google search for "DMS" and "database management system" returns ~16,000 results, whereas a search for "DBMS" and "database management system" returns ~335,000 results.
This issue occurs in the Core API section (and perhaps others).
Moreover, a DMS is a Document Management System, according to disambiguation of Wikipedia, while DBMS is a Database Management System.