jacket : Sometimes used as another term for dust jacket, a protective and often decorative wrapper, usually made of paper which wraps around the binding of a book

spine : The outer portion of a book which covers the actual binding. The spine usually faces outward when a book is placed on a shelf. Also known as the back.

bumping : Indicates that the affected part of the book has been impacted in such a way so as to cause a flattening, indention, or light bending.

first thus : Indicates that this is not the first appearance of a book in print, but that this is the first appearance in a substantially different format than the true first edition. For example, a first illustrated edition of a book, or even a first paperback release of a book originally published in hard cover.

shelf wear : Minor wear resulting from a book being place on, and taken from a bookshelf, especially along the bottom edge.