Guide

Bookbinding glossary

Bookbinding has its own vocabulary, and this page collects the words used across every method on this site: the paper units, the structural parts, the joining techniques and the hardware. Each definition traces to a conservation dictionary or a bookbinding craft source, listed at the end of the page, and stays in plain language rather than the source's own phrasing.

Published 2026-09-09 · Reviewed 2026-09-09

This glossary is part of the site's guides section.

8 terms

Paper units

Sheets, leaves, folds and the block they make.

Board: Board is a heavier, stiffer paper: paper and board sit on the same spectrum of stiffness rather than being two separate materials, and once a sheet gets heavy and stiff enough, binders stop calling it paper and start calling it a board.; See it on: Coptic binding, Smyth-sewn binding
Bolt: A bolt is the folded, uncut edge a signature that has not yet been trimmed open still carries at the head, the tail or the fore edge, and conservators have one word for that closed fold, whichever of the three edges it happens to fall on: a bolt.; See it on: Coptic binding, Pamphlet stitch, Saddle stitch binding, Smyth-sewn binding
Creep: Creep is what happens when paper held under steady pressure for a long stretch keeps easing into a new shape well after its first, almost instant flex has settled; that slow dimensional shift, sometimes called cold flow at room temperature, is called creep.; See it on: every method on this site
Fold: A fold is the crease running a sheet's length where it sits at the binding edge, not the head, tail or fore edge; folding a sheet in half creates that crease, distinct from the unrelated folded edges known as bolts.; See it on: every method on this site
Leaf: A leaf is one physical piece carrying two page faces, one on each side, produced by folding a printed sheet down to page size, whether or not both sides are printed.; See it on: Japanese stab binding, Coptic binding, Lay-flat binding, Perfect binding, Saddle stitch binding, Smyth-sewn binding
Sheet: A sheet is a single flat piece of paper, board or similar material, before it is folded, cut or bound into anything; every method on this site starts from sheets, whether they stay loose or get folded into a signature.; See it on: Comb binding, Perfect binding, Saddle stitch binding, Spiral binding, Japanese stab binding, Coptic binding, Pamphlet stitch, Screw-post binding, Smyth-sewn binding
Signature: A signature is a folded group of leaves nested inside one another, sewn or otherwise joined as one unit before several such groups are gathered into a text block; conservators also call the same unit a section.; See it on: Coptic binding, Pamphlet stitch, Saddle stitch binding, Smyth-sewn binding
Text block: The text block is the stacked leaves or signatures actually meant to be read: what remains once the cover and any endpapers a binder has added are stripped away.; See it on: Lay-flat binding, Perfect binding, Smyth-sewn binding

9 terms

Structural parts

Where a book bends, meets and is covered.

Cover: A cover is the outer wrap that protects a text block in use and storage, and often carries a title or decoration besides, whichever of the eleven joining methods on this site holds it to the pages.; See it on: every method on this site
Endpaper: An endpaper is a unit of two or more extra leaves a binder adds at the very front of a book and again at the very back, sitting between the covers and the text block itself.; See it on: Lay-flat binding, Smyth-sewn binding
Fore edge: The fore edge is the edge running opposite the spine, along the side a reader thumbs through to reach any page; it is sometimes called the front edge, though the shorter name binders and conservators settle on is fore edge.; See it on: every method on this site
Gutter: The gutter is the inner margin where two facing pages meet, right at the sewn fold of a signature.; See it on: Perfect binding, Saddle stitch binding
Head and tail: Head and tail are a bound book's top and bottom edges, running crosswise to the spine rather than alongside it the way the fore edge does, each one meeting the spine and covers directly; conservators name that pair together, the top one first.; See it on: every method on this site
Hinge: A hinge, in this site's own use, is the line where a book's cover meets its spine and has to flex every time the book opens. A conservation dictionary's own headword hinge names something else entirely, an internal strip glued in near the endpapers, not that external flexing line, which the same dictionary instead calls a joint.; See it on: Coptic binding, Lay-flat binding, Perfect binding, Screw-post binding, Smyth-sewn binding
Joint: A joint is the external seam where a case-bound cover meets the spine and has to bend every time the cover swings open. A conservation dictionary keeps a separate headword, hinge, for something else again, an internal reinforcement strip near the endpapers, and the same dictionary's most exact word for the external seam is joint.; See it on: Coptic binding, Lay-flat binding, Perfect binding, Screw-post binding, Smyth-sewn binding
Spine: The spine is the narrow edge of a book's cover that runs along the folded or bound side and faces outward on a shelf; sewing, adhesive or hardware all attach at this same edge, whichever method joins the pages.; See it on: every method on this site
Wraparound cover: A wraparound cover is a single folded sheet doing triple duty as the front cover, the spine and the back cover all at once, with no separate spine piece added.; See it on: Perfect binding, Spiral binding

5 terms

Joining techniques

How leaves and signatures are held together.

Adhesive binding: Adhesive binding is the technique this dictionary names for gluing loose leaves together at one edge into a single solid block, with no thread or stitching involved anywhere; the word describes the joining method itself, not any one product.; See it on: Lay-flat binding, Perfect binding
Kettle stitch: A kettle stitch is the linking stitch, near the head and tail of a sewn book, where the thread from one signature loops around the thread of the signature before it rather than piercing fresh holes of its own.; See it on: Coptic binding, Smyth-sewn binding
Punched holes: Punched holes are a row of evenly spaced openings through a stack of pages and its cover along one edge, sized to take a coil, comb, wire loop or post; that row starts as work done by a machine built for exactly one job, producing holes in paper.; See it on: Comb binding, Pamphlet stitch, Screw-post binding, Spiral binding, Japanese stab binding, Wire-O binding
PUR adhesive: PUR adhesive is the glue binderies reach for on long print runs because it flexes further and holds up better than the standard alternative, EVA.; See it on: Perfect binding
Sewing station: A sewing station is each single point along a folded signature where a needle pierces through and thread passes, one of several spaced out along that same fold; a whole row of them, sewn in sequence, links one signature to the next.; See it on: Coptic binding, Pamphlet stitch, Smyth-sewn binding, Japanese stab binding

4 terms

Hardware

Coils, combs, wires and posts that run through the holes.

Coil: A coil is one continuous spiral running through a row of punched holes, letting every page turn freely around it; the dictionary files the whole method under the broader label mechanical binding.; See it on: Spiral binding
Comb: A comb is this site's word for a molded plastic spine with a row of curved tines extending from it, closing through a matching row of rectangular holes to hold the leaves. Conservators classify the whole method as mechanical binding.; See it on: Comb binding
Double-loop wire: Double-loop wire is this site's name for two separate C-shaped wire loops squeezed shut through the same punched hole, rather than one single strand; the broader dictionary label for any wire-secured binding is simply wire binding.; See it on: Wire-O binding
Post: A post is a rigid two-piece barrel-and-cap fastener that screws together through a stack's punched holes, clamping pages and cover without any thread or adhesive; the dictionary defines the part generically as the threaded device used in a post binder.; See it on: Screw-post binding

2 terms

Opening states

The curated judgments the diagrams track.

Fold-back: Fold-back is the separate curated state this site tracks for whether a book's covers can keep rotating until they meet behind the stack, past merely open; the label names that specific, sourced judgment, not a measured hinge angle.; See it on: every method on this site
Opens flat: Opens flat is what this site's characteristics tables report for how far a binding's pages rotate before they stop, sorted into a plain yes, nearly, partially or no rather than a measured degree; every diagram is labeled representative, not a technical drawing of an exact angle.; See it on: every method on this site

References

Key references

cool.culturalheritage.org: Roberts and Etherington's conservation dictionary; most definitions here follow its entries
blog.papercraftpanda.com: A craft glossary of bookbinding terms; hand-binding usage for several words here
printingpartners.net: A commercial bindery's binding guide; the trade usage of the production terms

Every definition on this page traces to a fetched source, recorded with its URL and access date in the project’s research files; Methodology explains how sources are checked. Last reviewed 2026-09-09.