Question about UML
 

Hi everyone :)
I've just started learn UML and found a lot of useful info about use cases, class diagrams and so on. At the moment I am looking for more info about data dictionary and the format how it should be written... I've tried a lot of places but still no results.
I am particularly interested in data dictionary to support class diagram with detailed descriptions of all elements in the class diagram.
Maybe somebody knows and can explain a bit or at least where to look for some examples.