Cover Art; Book Jacket: A small poster advertising the book to potential readers. Authors who have failed to take into account the fact that it has been bound to the outside of the book, rather than printed on an interior page, will often come to the mistaken conclusion that it is meant to illustrate the story, and be distressed by its inaccuracy.
Earn Out: To the author, proof that the publisher didn't pay enough for the book.
E-book (electronic book): The publishing format that has the highest ratio of "time spent discussing it in meetings" to "copies sold."* Authors fondly believe that tens of thousands of readers who've passed up the opportunity to buy attractive, inexpensive hardcopy editions of their works will nevertheless go to great effort to illegally download wonky, badly formatted e-texts of the same books in order to read them in Courier on their computer screens.
Managing Editor: In trade book publishing, the person in charge of production. Normally, there are multiple layers of insulation between the author's behavior and the Managing Editor's production decisions. That's a good thing.
Mass Market: A smaller, cheaper edition of a hardcover novel that is nevertheless more difficult, expensive, and uncertain to publish.