Glossary
Footwear terms as factories use them. Where a term is regional or a common synonym exists, both are given.
Upper
Backstay — Vertical strip covering the centre-back heel seam. Common branding location.
Backer / scrim — Fabric bonded behind a thin upper material to stop stretch and fraying.
Bite line — The visible line where the sole unit meets the upper. One of the most scrutinised lines on a sneaker.
Collar — The padded ring around the ankle opening.
Eyestay / facing — The reinforced strip carrying the lace holes.
Foxing tape — Rubber band applied around the joint of upper and sole on vulcanized shoes.
Gusset — A panel joining the tongue to the vamp so debris can’t enter.
Lasting margin — The 12–18mm of surplus upper material below the bite line, used to attach the upper to the bottom.
Mean forme / standard — The flat master pattern derived by flattening a taped last. All panels derive from it.
Medial / lateral — Medial is the inside (arch side); lateral is the outside.
Mudguard — Raised panel wrapping the toe and lower sides.
Quarter — The side panel(s) between vamp and heel.
Skiving — Thinning a material’s edge so folds and overlaps don’t create bulk.
SPI — Stitches per inch. 7–9 typical for sneaker uppers.
Throat — The opening the tongue sits in.
Topline — The edge of the collar opening.
Vamp — The panel covering the forefoot and toes.
Inside
Counter — Stiff thermoplastic cup between upper and lining at the heel. Owns heel hold.
Lasting board / insole board — Stiff cellulose board used in board-lasted construction.
Shank — A stiffener under the arch.
Sockliner / footbed — The removable insert underfoot.
Strobel board — Fabric floor stitched to the upper’s lasting margin, forming a closed sock.
Toe puff / toe box — Thermoplastic reinforcement at the toe. (Note: “toe box” also colloquially means the toe area.)
Bottom
Blown rubber — Foamed rubber outsole. Lighter, softer, less durable than carbon rubber.
Carbon rubber — Carbon-black-filled rubber. The durability standard.
Cupsole — Outsole molded as a cup with walls; the upper is cemented inside it.
Drop / offset — Heel stack height minus forefoot stack height, in mm.
EVA — Ethylene-vinyl acetate foam. The common midsole material.
Featherline — The outline of the last’s underside; the sole must match it.
Gum rubber — Natural rubber, honey-coloured, grippy, marks and yellows.
Open mold / stock mold — An existing sole mold you can use without paying tooling.
Outsole — The ground-contact layer.
Phylon — Compression-molded EVA. The athletic midsole standard.
Shore A — Hardness scale for rubber. Sneaker outsoles typically 55–70.
Asker C — Hardness scale commonly used for foams. Sneaker midsoles typically 45–60.
Stack height — Total material thickness underfoot at a given point.
Toe spring — How far the toe lifts off the ground at rest.
Tooling — The machined molds that produce sole components. The main capital cost in footwear.
Wedge — A full-length midsole with heel elevation.
Lasts and sizing
Ball girth — Circumference at the widest part of the forefoot. The primary fit measurement.
Cone — The upper rear portion of a last, often removable to allow extraction.
Grading — Deriving a full size run from a single developed size.
Heel-to-ball length — Where the shoe flexes. Wrong value = painful creasing.
Instep girth — Circumference over the arch. Controls lacing tightness.
Last — The 3D form around which a shoe is built.
Long heel girth — Instep-around-heel circumference. Controls getting the shoe on.
Mondopoint — Sizing by actual foot length in mm. The unambiguous system.
Paris point — The EU size increment: 2/3 cm (6.67mm).
Sample size — The size everything is developed in. Typically US men’s 9 / UK 8 / EU 42.
Short heel girth — Around the heel. Controls heel slippage.
Stick length — Overall last length along the bottom.
Toe allowance — Extra last length beyond the toes. 10–20mm typical.
Construction
Board lasting — Lasting margin cemented onto a stiff insole board.
Cold cement — The dominant modern method: upper cemented to a pre-made sole unit.
Direct injection (DIP) — Sole material injected directly onto the lasted upper.
Lasting — Pulling the upper down over the last and securing it.
Slip lasting / California — Upper sewn to a sock lining and slipped onto the last. Very flexible.
Strobel lasting — Margin stitched to a strobel board with a Strobel machine.
Vulcanization — Curing rubber with heat and sulfur, fusing the sole assembly. Vans/Converse type.
Manufacturing & trade
AQL — Acceptable Quality Limit. The statistical standard for pass/fail inspection.
BOM — Bill of Materials. Every component, specified.
Clicking die — Steel-rule cutting die for a pattern piece. One per piece per size.
Confirmation / PP sample — The final approved sample; bulk is judged against it. Also “golden sample.”
DUPRO — During-production inspection.
FOB — Free On Board. Price with goods loaded at origin port.
Incoterms — Standard terms defining where cost and risk transfer.
Lab dip — A physical material sample dyed to your target colour, for approval.
LCL / FCL — Less than / full container load.
Landed cost — FOB plus freight, insurance, duty and clearance.
MOQ — Minimum order quantity.
Pull-over — An upper pulled over the last with no sole, for pattern and proportion review.
Proto / P sample — First development sample. Construction proof; materials often wrong.
PSI — Pre-shipment inspection.
Size curve — The distribution of quantities across sizes in an order.
SMS — Salesman sample, made in correct materials for selling and photography.
Tech pack — The complete technical specification document.
Yield — How efficiently pattern pieces nest on a material. A major cost driver.
Compliance
Chrome VI — Hexavalent chromium; a restricted substance that can form in improperly chrome-tanned leather.
GRS / RCS — Global Recycled Standard / Recycled Claim Standard.
HS / HTS code — Tariff classification code. Footwear is Chapter 64.
LWG — Leather Working Group; the recognised environmental audit standard for tanneries.
REACH — EU chemicals regulation governing substances in articles.
RSL — Restricted Substances List.
SATRA — Footwear research and test-method body; the source of many industry test standards.