Bunka
A compact all-purpose knife similar to a santoku, usually with an angled, pointed tip for detail work, scoring, and precise cuts.
TETSU & OAK KNIFE GUIDE
Japanese Knife Glossary
Japanese kitchen knives are often described with specialized terms for blade shapes, steels, finishes, geometry, handles, and sharpening. This glossary explains the language in clear, practical terms.
BLADE SHAPES
Common Japanese Knife Types
Blade shape determines the tasks, cutting motion, reach, and tip control a knife is designed to provide.
Deba
A thick traditional single-bevel knife used primarily for fish breakdown. It is not a general-purpose Western-style bone cleaver.
Gyuto
The Japanese interpretation of a Western chef’s knife. It is an all-purpose shape suited to vegetables, herbs, fish, and boneless meat.
Honesuki
A triangular Japanese boning knife designed for poultry fabrication and working around joints.
Kiritsuke
A term used for several long, pointed Japanese blade styles. Traditional single-bevel kiritsuke differ greatly from modern double-bevel kiritsuke-style gyuto.
Nakiri
A tall, rectangular double-bevel vegetable knife with a relatively flat edge for straight chopping and push cutting.
Petty
A small Japanese utility knife used for fruit, trimming, garnishes, herbs, and detailed preparation.
Santoku
A compact all-purpose knife commonly used for meat, fish, and vegetables. It is usually shorter and flatter than a gyuto.
Sujihiki
A long, narrow double-bevel slicing knife for meat, fish, roasts, and clean presentation cuts.
Usuba
A traditional single-bevel vegetable knife that requires specialized technique and sharpening.
Yanagiba
A long traditional single-bevel slicing knife used for sashimi and precise fish preparation.
Chinese Cleaver
A tall, broad knife used for slicing, chopping, and transferring ingredients. Thin vegetable cleavers are not intended for bones.
STEELS & MATERIALS
Common Steel Terms
Steel affects corrosion resistance, edge retention, toughness, sharpening feel, and required maintenance.
Aogami
“Blue paper steel,” a family of Japanese carbon steels alloyed for improved edge retention. Aogami #1, #2, and Super are different steels.
Carbon Steel
Steel with limited corrosion resistance that can sharpen finely but may develop patina or rust if left wet or exposed to acids.
Core Steel
The central cutting steel in a clad blade. The core is exposed at the edge and determines much of the knife’s sharpening and edge behaviour.
Ginsan
Also called Silver #3, a Japanese stainless steel known for good corrosion resistance and responsive sharpening.
HRC
Rockwell C hardness, a measurement used to describe steel hardness. Higher hardness can improve edge retention but does not alone determine quality or performance.
Molybdenum Stainless
A broad commercial description for stainless knife steels containing molybdenum. Exact performance depends on the specific alloy and heat treatment.
Reactive Steel
Steel that can discolour, patina, or rust through contact with moisture, salt, and acidic food.
Shirogami
“White paper steel,” a family of simple Japanese carbon steels valued for clean sharpening response and fine edges.
Stainless Steel
Steel formulated with greater corrosion resistance. Stainless does not mean rust-proof and still requires prompt cleaning and drying.
VG10
A popular Japanese stainless cutlery steel offering a practical combination of edge retention, corrosion resistance, and availability.
Sandvik 19C27
A fine-grained stainless cutlery steel used in kitchen knives for a balance of sharpness, wear resistance, and corrosion resistance.
420J2
A corrosion-resistant stainless steel often used for durable, approachable knives or as stainless cladding around a harder core.
CONSTRUCTION & GEOMETRY
How the Blade Is Built and Ground
Apex
The point where the two sides of the edge meet. Sharpening recreates and refines this extremely thin cutting line.
Asymmetrical Edge
A double-bevel edge ground more heavily on one side than the other. It should not automatically be sharpened equally on both sides.
Bevel
An angled surface ground into the blade. A knife may have small edge bevels, wide primary bevels, or a traditional single bevel.
Choil
The rear portion of the blade near the handle. Choil photographs often reveal thickness and grind behind the edge.
Cladding
Outer steel layered around a harder core. Cladding can improve corrosion resistance, toughness, appearance, or manufacturability.
Convex Grind
A slightly curved blade face or bevel that can improve food release, strength, and smooth cutting when executed well.
Distal Taper
The gradual reduction in blade thickness from the heel toward the tip. It affects balance, tip performance, and cutting feel.
Double Bevel
A blade sharpened from both sides. Most gyuto, santoku, bunka, nakiri, petty, and sujihiki are double-bevel knives.
Grind
The three-dimensional shaping of the blade faces and area behind the edge. Grind strongly affects cutting resistance and food release.
Hamaguri
A “clamshell” convex geometry commonly associated with some traditional Japanese blades and sharpening approaches.
Heel
The rear section of the cutting edge nearest the handle.
Primary Bevel
The larger ground surface that shapes the blade toward the edge. Terminology varies by maker and sharpening tradition.
Profile
The side-view shape of the cutting edge, including how flat or curved it is from heel to tip.
Shinogi
The ridge line separating the wide bevel from the upper blade face on many traditional Japanese knives.
Single Bevel
Traditional geometry with a large bevel on one side and a specially prepared back side. It requires specialized use and sharpening.
Spine
The unsharpened top edge of the blade. Spine thickness and taper affect stiffness, weight, and comfort.
Ura
The back side of a traditional single-bevel Japanese knife.
Urasuki
The shallow hollow ground into the back of many traditional single-bevel blades.
BLADE FINISHES
Surface Texture and Appearance
Finishes can affect appearance, surface character, and sometimes food release, but they should come after shape, geometry, and steel.
Damascus
A layered pattern created through multiple steels or decorative cladding. Damascus describes construction and appearance, not one specific steel or quality level.
Kasumi
A soft, mist-like finish traditionally seen where softer cladding and harder steel are polished differently.
Kurouchi
A dark forge-scale finish intentionally left on parts of the blade. It can provide rustic appearance and some protection to covered areas.
Migaki
A smooth, polished or satin-finished blade surface without a heavily textured forge finish.
Nashiji
A textured finish resembling the skin of a Japanese pear.
Tsuchime
A hammered surface finish. Hammer patterns vary and may provide visual texture and small pockets that can influence food release.
Hairline Finish
A directional satin finish made from fine parallel polishing lines.
Mirror Polish
A highly reflective blade finish. It can look striking but may show scratches and fingerprints easily.
HANDLES & STORAGE
Handle and Knife-Storage Terms
Ferrule
The collar between the blade and handle on many wa-handle knives. It may be made from wood, synthetic material, horn, or other materials.
Full Tang
A tang extending through most or all of a Western-style handle, often visible between the handle scales.
Hidden Tang
A tang inserted inside the handle and not visible from the outside. This construction is common with Japanese wa handles.
Pakkawood
A laminated wood-and-resin material valued for dimensional stability, moisture resistance, and consistent appearance.
Saya
A fitted wooden blade cover used to protect the edge and tip during storage or transport.
Tang
The portion of the blade that extends into the handle.
Wa Handle
A Japanese-style handle, commonly octagonal, oval, or D-shaped. It is often lighter than a Western handle.
Yo Handle
A Western-style handle, commonly built with scales and rivets around the tang.
SHARPENING TERMS
Whetstone and Edge-Maintenance Language
Burr
A thin fold of metal formed on the side opposite the stone when sharpening reaches the apex.
Deburring
The process of removing weakened burr material after the edge has been formed.
Flattening
Restoring a whetstone to a level surface using a lapping plate, flattening stone, or other suitable abrasive.
Grit
A numerical description of abrasive particle size. Lower numbers are coarser; higher numbers create finer scratch patterns.
Honing
Light edge maintenance that can refresh or realign some edges. Honing is not the same as full sharpening.
Lapping Plate
A flat abrasive plate used to level and maintain whetstones.
Micro-Bevel
A very small secondary bevel added at the edge to increase durability or simplify maintenance.
Sharpening
Controlled removal of steel to restore the cutting edge and recreate the apex.
Slurry
A mixture of water, abrasive particles, and metal swarf that forms on some whetstones during use.
Splash-and-Go
A stone designed to be used after wetting the surface rather than soaking for an extended period.
Stropping
Refining or deburring an edge on leather, fabric, wood, or another prepared surface.
Thinning
Removing material behind the edge to restore cutting performance when repeated sharpening has made the knife too thick.
Wire Edge
A thin, weak flap of metal that can feel sharp temporarily but folds or breaks away quickly if not removed.
CARE & PERFORMANCE
Ownership and Cutting Terms
Edge Retention
How long an edge continues cutting effectively before maintenance or sharpening is required.
Food Release
How easily cut food separates from the blade face. Grind, texture, ingredient moisture, and technique all contribute.
Patina
A stable grey, blue, purple, or dark surface reaction that develops on reactive carbon steel. It is different from active orange or red rust.
Rock Chopping
A motion where the tip stays near the board while the heel rises and falls. Curved gyuto profiles usually suit it better than flat nakiri.
Push Cutting
A cutting motion that moves the knife forward and down through the ingredient.
Wedging
Excessive splitting resistance caused by blade thickness, grind, ingredient density, or cutting angle.
CONTINUE LEARNING
Turn the Terms Into a Better Buying Decision
01
Choosing Your First Knife
Use the terms to compare shape, length, steel, handle, and budget.
02 Knife Types GuideCompare the practical uses of Japanese blade shapes.
03 Knife Steel GuideUnderstand maintenance, corrosion resistance, and edge behaviour.
04 Knife Care GuideLearn cleaning, storage, cutting-board, and rust-prevention habits.
STILL UNSURE ABOUT A TERM?
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Send us the product name or terminology you are comparing, and we’ll explain what it means for actual kitchen use.