# Packaging glossary: dielines, materials and print terms > Understand 40 packaging terms with practical examples, production checks and links to editable templates and tools. Canonical: https://dielinemaker.com/glossary Last updated: 2026-10-26 ## Geometry - [Dieline](https://dielinemaker.com/glossary/dieline) — A dieline is a flat drawing that identifies where a package is cut, creased, perforated and assembled. - [Blank](https://dielinemaker.com/glossary/blank) — A blank is the flat piece of material cut to shape before it is folded or assembled into packaging. - [Cut line](https://dielinemaker.com/glossary/cut-line) — A cut line indicates a path where material is intended to be cut through, such as a package outline or window. - [Crease](https://dielinemaker.com/glossary/crease) — A crease is a controlled deformation of board that guides a fold without cutting through the material. - [Perforation](https://dielinemaker.com/glossary/perforation) — A perforation is a series of cuts separated by uncut bridges that creates a controlled tear or separation line. - [Glue flap](https://dielinemaker.com/glossary/glue-flap) — A glue flap is an extra strip of a packaging blank that bonds to another panel to form a seam. - [Inside dimensions](https://dielinemaker.com/glossary/inside-dimensions) — Inside dimensions describe the space within an assembled package, rather than its external footprint. - [Outside dimensions](https://dielinemaker.com/glossary/outside-dimensions) — Outside dimensions describe the external envelope of an assembled package, including its material thickness. ## Materials - [Caliper](https://dielinemaker.com/glossary/caliper) — Caliper is the measured thickness of a sheet material, commonly expressed in millimetres or micrometres. - [Grammage (gsm)](https://dielinemaker.com/glossary/grammage) — Grammage is the mass of a sheet material per unit area, normally stated in grams per square metre (g/m² or gsm). - [Paperboard](https://dielinemaker.com/glossary/paperboard) — Paperboard is a relatively thick paper-based sheet used for applications such as folding cartons, sleeves and backing cards. - [Corrugated board](https://dielinemaker.com/glossary/corrugated-board) — Corrugated board combines one or more fluted paper layers with flat liners to create a lightweight structural sheet. - [Flute](https://dielinemaker.com/glossary/flute) — A flute is the wave-shaped paper layer within corrugated board; flute profiles describe its height and spacing. - [Grain direction](https://dielinemaker.com/glossary/grain-direction) — Grain direction is the predominant alignment of fibres in a paper or board sheet. - [Coating](https://dielinemaker.com/glossary/coating) — A coating is a surface layer applied to paper, board or printed artwork to change its finish or performance. - [Lamination](https://dielinemaker.com/glossary/lamination) — Lamination joins a separate layer, often a film, to a substrate to create a combined material. ## Structures - [FEFCO code](https://dielinemaker.com/glossary/fefco) — A FEFCO code identifies a corrugated packaging construction using a shared design-style reference. - [ECMA code](https://dielinemaker.com/glossary/ecma) — An ECMA code identifies a folding-carton design style in the European Carton Makers Association’s classification. - [Tuck end](https://dielinemaker.com/glossary/tuck-end) — A tuck end is a carton closure whose main flap has a tongue that slides inside the carton body. - [Reverse tuck end](https://dielinemaker.com/glossary/reverse-tuck-end) — A reverse tuck end carton has its top and bottom main closure flaps attached to opposite body panels. - [Straight tuck end](https://dielinemaker.com/glossary/straight-tuck-end) — A straight tuck end carton has its top and bottom main closure flaps attached to the same body panel. - [Crash-lock bottom](https://dielinemaker.com/glossary/crash-lock) — A crash-lock bottom is a pre-glued carton base designed to form as the flattened carton body is opened. - [Mailer box](https://dielinemaker.com/glossary/mailer-box) — A mailer box is a packaging format commonly assembled from one blank with a hinged lid and interlocking walls or tabs. - [Packaging sleeve](https://dielinemaker.com/glossary/sleeve) — A packaging sleeve is an open-ended wrap that fits around a product, tray or inner box. ## Artwork - [Bleed](https://dielinemaker.com/glossary/bleed) — Bleed is artwork extended beyond the intended cut boundary so small cutting variations do not expose an unprinted edge. - [Safe area](https://dielinemaker.com/glossary/safe-area) — A safe area is a region set inward from cuts, folds or other risks where important artwork should remain. - [Trim](https://dielinemaker.com/glossary/trim) — Trim is the intended finished boundary of printed work after excess material is cut away. - [Quiet zone](https://dielinemaker.com/glossary/quiet-zone) — A quiet zone is the clear margin around a barcode that lets a scanner distinguish the symbol from surrounding graphics. - [Spot colour](https://dielinemaker.com/glossary/spot-color) — A spot colour is a named colour separation handled independently from process colour channels in a print file. - [Overprint](https://dielinemaker.com/glossary/overprint) — Overprint is a print instruction to retain underlying colour when another object is printed over it. - [Trapping](https://dielinemaker.com/glossary/trapping) — Trapping is a small overlap between adjacent printed colours intended to hide gaps caused by registration variation. - [Packaging proof](https://dielinemaker.com/glossary/proof) — A packaging proof is a review version used to check a defined aspect of a design before production. ## Production and files - [Imposition](https://dielinemaker.com/glossary/imposition) — Imposition arranges one or more designs on a production sheet for printing and subsequent cutting or finishing. - [N-up](https://dielinemaker.com/glossary/n-up) — N-up states how many copies or positions of a design are placed on one production sheet. - [PDF](https://dielinemaker.com/glossary/pdf) — PDF is a document format used to exchange fixed-layout pages containing artwork, text and production information. - [SVG](https://dielinemaker.com/glossary/svg) — SVG, Scalable Vector Graphics, is an XML-based format for two-dimensional graphics including paths, text and images. - [DXF](https://dielinemaker.com/glossary/dxf) — DXF is Autodesk’s drawing interchange format, used to transfer drawing entities between CAD applications. - [CF2 / CFF2](https://dielinemaker.com/glossary/cf2) — CF2 is the common file extension for CFF2, a packaging CAD interchange format used for structural design data. - [JDF](https://dielinemaker.com/glossary/jdf) — JDF, Job Definition Format, is a CIP4 format for describing print products, production processes and related job information. - [XJDF](https://dielinemaker.com/glossary/xjdf) — XJDF, Exchange Job Definition Format, is CIP4’s XML-based format for exchanging print-job information between applications. ## Put the terms into practice Follow a packaging workflow or start with a template sized around your product. ## Related - [Step-by-step guides](https://dielinemaker.com/learn) - [Dieline templates](https://dielinemaker.com/dielines) - [Industry buying guides](https://dielinemaker.com/industries)