A productname is the formal name of any product. Identifying a product this way may be useful if you need to provide explicit disclaimers about product names or information.

For example, the copyright statement in most books includes a notice similar to this:

Many of the designations used by manufacturers and sellers to distinguish their products are claimed as trademarks. Where those designations appear in this book, and O’Reilly Media, Inc. was aware of a trademark claim, the designations have been printed in caps or initial caps.

If every product name were coded as a productname, you could automatically generate a complete list of all the product names and mention them explicitly in the notice.

In running prose, the distinction between an application and a productname may be very subjective.

application, copyright, database, filename, hardware, trademark