Advance Reader's Copy (aka Advance Review Copy or ARC) - A pre-publication copy of a book distributed by a publisher generally publicity or review purposes. ARCs are typically in softbound wrappers, either with the dust jacket art of the first trade edition or merely printed text. ARCs may also include an uncorrected proof printed for editorial corrections. The text may differ from the first trade edition, and ARCs often represent the true first edition of a book.
AEG (aka a.e.g.) - All edges gilt, meaning the top, fore-edge and foot of the text block are all colored in gold.
ALS - Autographed signed letter.
Association Copy - A book once owned by the author, or a book signed, inscribed, or including annotations by the author to someone of note, or a book owned by someone who is closely related to the subject matter of the book (i.e. an actor's copy of a book made into a movie)
Backstrip - The material used by the binder to reinforce the sheets in the binding of the spine. Often, this term is used to refer to the portion of the binding on the spine.
BAL - Bibliography of American Literature (American books prior to 1930), compiled by Joseph Blanck in 9 volumes.
Bibliography - A reference work on books consisting of a certain subject or by a certain author. These references works are utilized by booksellers such as Nelson Rare Books, librarians, and discerning collectors to verify the authenticity of an edition, issue, or state of a book.
Bibliophile - A lover of books. See A Gentle Madness by Nicholas Basbanes for a modern and amusing take on book collectors.
Binding - The material which is used as a protective cover for the book, normally leather, cloth, vellum, paper, or buckram.
Blind (-stamping or -tooling) - An impression into the paper or the binding without gilt or other coloring, leaving the impression only. Conversely gilt-stamping or gilt-tooling leaves an impression along with gold coloring, and is frequently found in leatherbound books.
Boards - The term for the front and back covers of the book.
Book Club Edition (aka BCE or BOMC) - Editions of books published by book clubs. In most instances, BCEs are not the first editions of a book. BCEs are often readily identifiable by being smaller that the first trade edition and often identify themselves as BCEs on the dustjacket. Nelson Rare Books generally does not carry BCEs (unless they have other intrinsic value), and notes any instance when carrying the same.
Dust Jacket (aka dustjacket, dustwrapper, dust wrapper, DJ, DW, or book jacket) - A separate covering for a book. While present in a small number of books prior to the 1920s, dust jackets became much more prevalent in the latter two thirds of the twentieth century. Given their fragility and as they are easily discarded, the absence of a dust jacket (where one is called for) is often extraordinarily detrimental to value of a book and books missing jackets are normally considered incomplete.
Book Plate (aka ex-libris) - A label of the book's owner. Bookplates can increase the value of a book given a prominent former owner or a collectible book plate designer, but may decrease a book's value if the same are not present.
Broadside - Materials printed on one side only, frequently found in advertising materials or public notices.
Bumping - When the corners or the spine ends of a book have been damaged.
Chipping - Damage where small pieces which have chipped off of a binding or a dust jacket.
Closed tear - A tear where no materials are missing (as opposed to a tear where a portion of the page is missing).
Cocked - When the corners of the book are not square, often due to a book having been previous read or incorrectly shelved. From the vantage point of looking down at top edge of the book, the spine will look slanted.
Collate - To verify that the book is complete. For modern books, collation usually entails ensuring all numbered and [unnumbered] pages are present, for earlier books I will leave that the expertise of Philip Gaskell's A New Introduction to Bibliography or Fredson Bowers's Principles of Bibliographical Description.
Colophon - Information inserted by the publisher at the rear of a book, frequently containing the printer's device, place of publication/ printing press, number of copies of a limited edition, and the typeface used. Unusual in modern books apart from private presses.
Contemporary Binding - A binding that was placed on a book at or around the time of publication. While almost all modern books come pre-bound, until the mid-nineteenth century, books were published unbound, or in hard paper wrappers or boards, and which the buyer would have custom bound, often to match the rest of his or her library.
Dampstain - A stain, often white when left on the boards, and often brown when left on the pages, due to the book's over exposure to water.
Device - The printer's logo, arguably the most famous being the Aldine anchor, and more recently William Morris's Kelmscott press device.
Disbound - The opposite of bound! A book which has been removed from the binding (whereas unbound refers to materials which were never bound).
Dog-Eared - Pages which have been creased, frequently as a reader's make-shift bookmark.
Edge - The three outer sides of the book: the top edge (or head), the fore edge, and the bottom edge (or foot).
Edition - an edition is all of the copies of a book printed from the same type setting, all at once or even over a period of time, without major changes, although minor changes, may be made and are still considered as part of the same edition. Collectors and booksellers describe the differences in the same edition as different states or issues. When referring to a first edition, booksellers and collectors usually refer to the first state/printing/issue of a first edition.
Endpapers - The leaves constituting the pastedowns and free endpapers (aka ffep, fep, rep, frep) inside the front and rear covers.
Ephemera - Typically, though not necessarily, printed materials of generally of interest for only a short period of time (i.e. certain broadsides, posters, advertisements, etc.).
Errata - A list of errors and their respective corrections, which were found subsequent to the publication of a book. Errata are typically tipped in or pasted onto an endpaper by the printer. When an errata slip is called for, same should be present to constitute a complete book.
Ex-Library or Ex-Lib - A book deacassessioned from a public or private organization's library or collection (i.e. former New York Public Library, former monastery library, or former Union League).
Ex-Libris - From a private library, often indicated as such by a bookplate, stamp, or pen/pencil signature.
First Edition - The first printing/issue/state of a book, created from the first type setting. Although a librarian may refer to this term for any of the printings of a book, done from the first type setting, booksellerrs and collectsor use the term in a different manner, refrring only to the very first printing/state.
Fly-Leaf (aka Blanks) - blank papers at the front of the book after the endpapers and and the end of the book before the endpapers.
Foot - the bottom of the text block.
Fore-edge - The middle edge of the text block which is opposite of the spine. Fore-edges may be painted such that when fanned out, an image becomes visible.
Foxing - Brown/tan blotches in the paper caused by impurities in, or the low quality of, the paper.
Free Endpaper (fep, ffep, rep, frep) - Blank pages added to the front and rear of the book.
Frontispiece - An illustration, frequently an engraving, opposite the title page.
Ghost - Boo! A discoloration of the surface due to tape, sticker, or glue, which have chemically reacted with the paper.
Gilt Edges - Page edges which are painted with gold leaf for vibrancy.
Glassine - A transparent tissuepaper-like paper often used in place of a dust jacket, found primarily in private press books or limited editions.
Half Bound (often half-leather, half-cloth) - A book in which the spine and corners have been bound in one material (frequently leather or vellum) and the remainder bound in another material (frequently cloth or paper).
Half-Title - The page prior to the full title paper, which normally lists only the title of the book.
Head - The top edge of the text block.
Hinge - The place on the book where the boards meet the spine.
Impression - All copies of a particular book printed during a single run of the press.
Incunabula (aka incunable) - An early book printed prior to 1501.
Inscribed - When an author or figure associated with a book writes more than a mere signature (ex. "To Nelson Rare Books, with greatest appeciation, William Morris").
IOBA - The Independent Online Booksellers Association, being an international trade group committed to high ethical standards for online booksellers. Nelson Rare Books is proudly a member of IOBA!
ISBN - A unique identifying number used in more than 150 countries to identify books published after the late 1960s.
Issue - A change, made after the book has been published, in the text or in the binding. In referring to a first edition, book collectors and booksellers usually refer to the first issue of a first edition.
Laid-In - Something that is not attached to the book.
Loose - When the binding and text block have become loose, normally due to carelessness in reading or mishandling.
Manuscript - Written by hand.
Marbled - Boards or endpapers, which are decorated in a manner as to resemble marble.
n.d. - No Date, meaning the book does not include the date of publication.
n.p. - No Place, meaning the book does not include the place of publication.
OCLC / Worldcat - An online conglomerate of over 40,000 libraries sharing data and catalogs. Booksellers and collectors often refer to OCLC or Worldcat to determine the rarity/scarcity of a particular book and whether same is found in any member library.
Open Tear - a tear in which a portion of the page is missing.
Pastedown - The portion of the endpaper which is glued to the inside of the front and rear boards.
Pg. / pp. / p. - Page or pages.
Plate - A page or portion thereof containing an illustration.
Points - Particular features in a published book which assist in determining editions, states, impressions, or issues.
Presentation Copy - A book inscribed, generally by the author, to someone else on a day or place of significance or for a particular reason.
Price Clipped - The price on the dust jacket has been cut off.
Provenance - A history of the ownership of a particular book, as evidenced by prior owner's inscriptions, auction and booksellers' records, bookplates, etc. Especially rare books are often referred to by collectors and booksellers by a particular owner.
Publisher's Binding - A binding provided by the publisher, which while exceedinly common today, was much rarer in the past when buyers had bindings customized for their particular collection/library.
Quarter Bound - A book in which the spine is bound in a different material (frequently vellum or leather) than the rest of the book.
Rebacked - A repair in which the spine has been replaced. When the backstrip remains present, booksellers often note that a book has been rebacked with original spine present.
Rebound - A repair in which the entire binding is replaced.
Recased - A repair in which the book has been taken apart and put back together with the original parts, which is usually done to tighten up a loose book.
Recto - The right hand page. Opposite the verso.
Remainder Mark - A new book returned to the publisher as unsold, and which is often identified with a line or dot made by a permanent marker or polka dotted spray on the top or foot edges.
Review Copy - A copy which has been sent by the publisher or author free of charge for the purposes of review, often including a postcard or letter requesting the same. Although often pre-publication, review copies are not necessarily first editions.
Rubbed - Damage in which the color has been worn of the binding or dust jacket. Frequently also including when the cloth covering paper boards has worn away exposing the paper underneath.
Separate - When the joints or hinges have separated from the spine and may be held on only by the endpapers.
Shaken - Damage in which the text block is loose, but not detached, from the binding.
Shelf-Wear - Damage in the form of slight scratches to a book or dust jacket due to being shelved next to other books which have not been protected by a mylar cover.
Signed - A book which only the signature is present and no further inscription.
Slipcase - A box with three sides, often of cardboard or cloth-covered cardboard, to house a book while leaving the book's spine showing.
Spine - The back of a book where the title, if called for, is present when on a shelf.
Starting - When the hinges or the joints are beginning to tear or separate.
State - Variations within an edition, which are made prior to publication.
Sunning - Yellowing, browning, or fading of the paper, dust jacket, or binding due to sun exposure.
t.e.g. - Top edge gilt.
Text block - The pages of a book containing content but which does not include the endpapers.
Tipped In - Material glued into the book but only by a small portion (i.e. think of a permanent post-it note).
Title Page - The page near the front of the book in which the title, author, publisher, and other important information are contained.
TLS - Typed letter signed.
Tooling - The decorations on a binding. See gilt.
Top Stain - A colored stain on the top edge of the text block.
Trade Paperback - a large paperback, normally an early printing of a paperback edition, not a mass-market paperback.
Trade Edition - An edition sold to the general public, rather than for private or limited distribution. Booksellers and collectors frequently use this term to refer to an edition of a book subsequent to a first, limited edition.
Unbound - A book which was never bound (as opposed to a book having been bound and then dismantled).
Uncorrected Proof / Proof Copy - A pre-publication printing intended for editorial or review purposes, and which is generally found in plain paper wrappers. See also Advance Reader's Copy as the same sometimes overlap.
Uncut - Edges which are rougly cut, as opposed to being uniformly trimmed by the binder or publisher.
Unopened - May refer to a book which has never been opened by a reader, and generally refers to a tight copy of a book. Same may also refer to a book in which the edges remain joined together and have not been cut open.
Vol. / Vols. - Volumes.
Variant - A copy of a book which in some manner differs from a reference copy, and may have a different binding, plate, etc.
Vellum - The skin of a calf which has not been tanned and is used for manuscripts, printing, or as material for a binding.
Verso - The left hand page of a book, opposite the recto.
Watermark - An identifying design, mark, or device in the paper, visible when held up to light.
Woodcut - An illustration produced by a plate made of wood.
Wrappers (aka wraps) - The covering of a book bound in paper.
For additional, and much more comprehensive definitions (in a highly readable book), see ABCs for Book Collectors by John Carter, which the ABAA has graciously provided on their website in PDF format.