This book has 4 parts. Part 1, Background, contains an UML Overview - UML summary, goals, complexity, assessment and concept areas - and a short overview on models, their meaning and purposes. Part 2, UML Concepts, contains an UML Walkthrough that summarizes all UML views, followed by short chapters on each one of the views, one on Profiles and one on the UML Environment. Part 3 contains the Reference. Part 4 contains appendices.
Part 3, the Reference, actually what the book has been edited for, contains a Dictionary of Terms listed in alphabetical order. Each entry is structured as follows: The entry name, a short definition of a few sentences, the semantics of the term, its notation and, as necessary, a discussion and the history.
This is a reference book, not a user's guide nor a tutorial. It acts as a dictionary to UML terms and mainly follows the same principles as for an English language dictionary. It's not unusual for a definition sentence of an entry to call another entry that in turn calls another one, and so on. Entry descriptions are mostly given in text form, with the support of figures wherever necessary. Language is often elaborate, not always straightforward. However, taken into account the detailed terms coverage and description provided in this book, few of them really remain inaccessible.
As for an English language dictionary, the linear reading of this book will be of little help to the learning of the language.