Warhammer 40k - Lexicanum:Printable version
The Printable version tool specifies a style and layout of a Lexicanum page that is suitable to print the page in question. Your browser's print function should automatically use these presets when you print an article. This obviously not only applies to physical printing on paper but also when applicable to creating for example a PDF version of a Lexicanum page for digital use.
The Printable version tool can be accessed from the Tools tab at the left side of the screen.
More on the Printable version Wikimedia tool can be found here.