Board Thread:News and Announcements/@comment-4548390-20170306230733/@comment-4548390-20170405010122

Apocalypse Wars wasn't a crossover but a thematic event focused only on the X-Men family of titles. The Clone Conspiracy was a crossover focused only on the Spider-Verse family of titles. Spider-Women was a crossover focused on a subsection of the Spider-Verse family of titles (the Spider-Women family of titles). Monsters Unleashed was just a minor event. WMD is a more classical looking crossover focused on titles written by the same writer (Greg Pak).

I believe there's already a name for them:
 * Line-wide crossovers/events for the largest ones (like Secret Wars, Civil War II, and Secret Empire);
 * Family-line crossovers/events for minor stories focused on a specific family of titles (like Avengers Standoff!, Spider-Women, and Dead No More: The Clone Conspiracy);
 * Crossovers for books that have nothing to do with one another (with the exception of the writer and/or artist in some cases);
 * Team-ups usually being used for comics books where two characters, well, team-up;
 * Guest appearance for when a character appears in another character's book (as explained in one of the commentaries above);
 * Thematic event for when titles don't really crossover but there is a common link between them in the story (like Apocalypse Wars and Fall of the Mutants);