Glossary of Terms:

A beautiful and very durable top-quality, natural grain leather. Strong yet supple, it is used for the finest bindings. Traditionally known as Morocco leather.
Calfskin leather
A traditional high-quality leather used in fine bindings. It is long-lasting and its suppleness increases with use. Cambridge calfskin bindings use only top-grain leather.
French Morocco
Leather taken from a split calfskin, slightly thinner than other grades and therefore flexible and soft even when new. A French Morocco binding offers high-quality real leather at an economical price
Calf split leather
A superior grade to French Morocco leather, tanned to approach the quality and feel of full-grain calfskin leather.
Leather taken from a split calfskin, slightly thinner than other grades and therefore flexible and soft even when new. A French Morocco binding offers high-quality real leather at an economical price.
Art-gilt edges
A decorative finish to the page edges in which a red dye and gilt foil combine to add richness and lustre to the finished volume.
Bible paper
Thicker than India paper, but still much thinner than common book papers.
Gilt edges
A decorative finishing style in which a gold-coloured metallic foil is applied to the edges of the pages after they have been cut and rubbed smooth. Silver foil is often applied to the page edges of volumes bound in white. See also art-gilt edges.
Gilt line
A plain gold line or ‘frame’ on the inside covers.
India paper
The paper traditionally used for the best quality Bibles. The name is now generally used for papers that weigh less than 30 grams per square meter
Reference Edition
A Bible that includes cross-references to guide the reader to other parts of the Bible where similar subjects are treated. Footnotes also give variant readings of the text. Reference editions often include a concordance, maps and other study material.
Text Edition
A Bible in which the text only is provided, without cross-references.
Yapp/Semi Yapp
A bookbinding having soft edges that project beyond and fold over the edges of the pages to protect them.
Pronunciation marks
Some Bible texts incorporate a phonetic system for indicating the way difficult names should be pronounced, showing the vowel sounds and stressed syllables, as in a dictionary. These volumes are sometimes called ‘self-pronouncing’.
Some Bible texts have italicized the words that are not a part of the orginial languages.
The technical word is ‘overcasting’ for the extra line of vertical stitching which is inserted at the middle of the first section and sometimes the middle of the last section to add strength to the binding.  A sign of expert binding.  This process used to be standard for Cambridge Bibles, however, it used almost exclusively with Allan Bibles.  Please do not mistake this for a defect.  Here is a picture
Smyth Sewn Binding
Smyth Sewn (also known as Section Sewn) book bindings are the highest quality book binding available on the market today. It is the hallmark of library quality, archival safe books because the pages are physically sewn into the book using binders thread and further reinforced with fabric backing and adhesive to create the most usable and durable books available.  Look closely at the binding where the pages meet the spine and you can see the folds of the page signatures. Open the book to the middle of a signature and you may be able to see the binding thread stitches. Smyth Sewn bindings use thread to sew through folded signatures of a book. Signatures are made by printing on large sheets and then folding into groups of pages, usually 16 or 24 at a time. Each signature is sewn individually with threads going through each page several times. The threads are then tied off. All of the signatures are likewise attached together with thread creating what is called the book block. The book block is further strengthened using flannel and adhesive on the spine.