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.

8vo : Short for Octavo, A book whose page size is approximately 8-10 inches tall. The size is based on a sheet of paper 25 inches by 38 inches, the size of paper traditionally used by book printers, which has been folded and cut into 16 pages.. Unfortunately often misunderstood to mean 8 volumes.

crisp : A term often used to indicate a book's new-like condition. Indicates that the hinges are not loosened. A book described as crisp will not have 'well-read' pages, i.e., where the book will naturally open to certain pages or sections.