If you want to be an antiquarian, you have to speak the language.  Herewith, we offer a list of the most frequently encountered terms and abbreviations.

•  Advance Review Copy - A complimentary advance copy of a new book often sent to reviewers, usually a soft cover.
• aeg - all edges gilt.  See also teg.  Interestingly, this wasn't just for show - Gilding the edges of pages retarded browning - clever, eh?
• Annotated - Includes critical and explanatory notes.
• Antiquarian - Old and/or rare books, or a dealer of same.
   Antique Book - not an accepted term, and one which no book collector or bookseller should ever allow to pass his or her lips.  It is a phrase both jarring and meaningless, and you will do a great service to mankind if you will immediately make a point of correcting any unfortunate soul who uses it. 
• Appendix - The additional or supplementary material usually found at the end of a book.
• Author Copies - Complimentary copies of the first edition of a book given to the author by the publisher.
• Backbone - A book's backstrap, backstrip or spine.
• Bar Code - The common term for Universal Product Code.
• Boards - The stiff front and rear panels of a hardcover book.
• BOMC - Book of the Month Club edition. 
• Book Club Edition - As a general rule, book club editions are less desirable than regular editions. 
• Bound Galley - An uncorrected galley proof distributed by the publisher before publication.
• Casebound - A hardcover book.
• Chipped - A dust jacket that has small pieces chipped away at the edges.
• Clothbound - A book with cloth covering the boards.
• Colophon - Information about the book's publication printed at the end of the book.
• Deaccessioning - Selling or disposing of books from a collection.   Librarians use the simpler and more descriptive term "weeding."
• Dust Cover - See dust jacket.
• Dust Jacket - The paper covering the boards of a book.
• Dust Wrapper - See dust jacket.
• Edition - All the copies of the book made from a specific set of type.
• Embossing - A process which produces decorations raised above the surface (typically of printable material).
• Endpaper - There are two sorts of endpapers.  The folded sheet of paper pasted to the inside of the front or back cover is known as a paste-down endpaper or, less formally, a paste-down.  The first and last free pages of a book, usually blank, are known as free endpapers.
• Ex Library (ex-lib) - A book with library markings on it.  Generally less desirable.
• Facsimile - An exact reproduction of an original book depicting the original text and the book's physical appearance.
• First, First Edition - The first printing of the book from a collectors perspective.
• First American, First US - First edition printed in the United States of America.  Generally, this term is used when a book has been printed first elsewhere, e.g., the United Kingdom. 
• Flyleaf - Unprinted pages at the front or rear of a book.
• Fore edge - The front of a book -- the spine is the back of a book.
• Foxed - Discolorations, usually with reddish-brown spots on the pages of a book.
• Frontispiece - Illustration which faces the title page.
• Galley - A proof copy of a book -- generally without page numbers.
   Gutter - White space between facing pages.
• Headband - A decorative strip added to the top or bottom of a book's spine.
   I.P. - In print.
• Impression - The number of books printed during a press run, or the run itself. A first impression is a first edition.
• Imprint - The publisher's and/or printer's note usually found at the bottom of the title page giving place, date and publication information.
• Limited Edition - A print run limited to a specific number. Often inscribed with the author's signature and a sequence number.
• O.P., OOP - Out of print.
• QPBC - Quality Paperback Book Club. 
• Shaken - A very loose binding.
• Softcover - generally, a paperback. 
• Stacked - A book with a shifted binding.
• teg - top edge gilt.