Knife Terms Glossary

Kitchen knife writing is full of Japanese loanwords, German compound nouns and sharpening jargon that nobody defines. Everything below is a term we use somewhere on this site, defined plainly. Blade shapes first, then construction, then steel, then sharpening.

Blade shapes

Gyuto — The Japanese chef’s knife. An all-purpose double-bevel blade, typically 180–240 mm, with a curved belly and a fine tip. The direct equivalent of a Western chef’s knife, usually in harder steel and a thinner grind. See the gyuto guide.

Santoku — “Three virtues” — meat, fish and vegetables. A shorter (165–180 mm), flatter all-purpose knife with a blunt sheepsfoot tip. Suits push-cutting rather than rocking.

Nakiri — A tall, rectangular, double-bevel vegetable knife with a dead-flat edge and no tip. Built for straight-down chopping. See the nakiri guide.

Usuba — The single-bevel professional version of a nakiri. Handed (separate left and right models), needs specialist sharpening, and not a sensible home purchase.

Petty — A small Japanese utility knife, roughly 120–150 mm. The gap between a paring knife and a gyuto.

Deba — A thick, heavy single-bevel Japanese knife for breaking down fish. Not a general knife and not for bone-in meat.

Yanagiba — A long, narrow single-bevel slicer for sashimi. One-directional pull cuts.

Bunka — A gyuto-length knife with an angled reverse-tanto tip instead of a curved point. Between a gyuto and a santoku in character.

Caidao (Chinese chef’s knife) — The thin, tall rectangular Chinese slicing knife, often mistaken for a cleaver. A genuine general-purpose knife. See chef knife vs cleaver.

Cleaver (meat) — A thick, heavy, obtusely ground chopper built to survive impact with bone. A different tool from a caidao entirely.

Construction

Tang — The portion of the blade steel that extends into the handle. A full tang runs the whole length and width; a partial or rat-tail tang runs only part way and is a weaker join.

Bolster — The collar of steel between blade and handle on many forged Western knives. Acts as a finger guard and adds balance, and blocks the heel of the edge when sharpening. A half bolster stops short of the edge; a full bolster runs down to it.

Forged — Hammered or pressed from a thick billet. Produces a heavier blade, allows a bolster and full tang. Does not itself make the steel harder — that comes from heat treatment.

Stamped — Cut from rolled steel sheet. Lighter, thinner and cheaper than forged, with no bolster. Not a mark of poor quality — many professional knives are stamped.

San-mai — “Three layers”: a hard core steel clad between two softer outer layers, so the edge can be very hard while the blade overall stays tough. The standard construction for clad Japanese kitchen knives.

Damascus — On a modern kitchen knife, decorative patterned cladding folded around a core steel. The core does the cutting; the layer count is cosmetic and does not indicate performance.

Kasumi — A traditional Japanese construction and finish where hard carbon steel is forge-welded to softer iron, producing a hazy contrast at the bevel.

Kullenschliff / granton / hollow edge — The oval scallops ground into the blade faces. They break suction so wet slices release; they do not affect sharpness.

D-handle (wa-style influence) — A contoured Japanese handle shaped with a flat and a ridge, usually oriented for a right hand. Comfortable if it fits you, awkward if it does not.

Pakkawood — Resin-impregnated laminated wood used for handles. Durable and stable, and more slippery than a textured polymer when wet.

Santoprene / Fibrox — Grippy thermoplastic handle materials used by Mercer and Victorinox respectively. Unattractive and the best-performing handles on the market with wet hands.

Steel and hardness

HRC (Rockwell C) — The standard hardness scale for knife steel, measured by how far a diamond indenter penetrates under load. Kitchen knives typically run ~55–58 HRC (German) or ~60–62 (Japanese). Higher means longer edge retention and more brittleness.

X50CrMoV15 — The near-universal German cutlery stainless: chromium, molybdenum and vanadium in a 0.5% carbon steel. Tough, corrosion-resistant, easy to sharpen, typically hardened to 55–58 HRC.

VG10 — A Japanese stainless with cobalt and vanadium, commonly used as a clad core and hardened to around 60 HRC. The workhorse of mid-priced Japanese knives.

VG-MAX — Kai’s upgraded VG10-family steel, used in Shun’s Classic line at around 60–61 HRC.

FC61 — The fine-carbide stainless core used in Miyabi’s Kaizen II line, around 60 HRC.

Shirogami / Aogami (White / Blue steel) — Traditional Japanese high-carbon steels. Take an exceptionally keen edge and rust readily — they must be dried immediately.

Carbon steel — Non-stainless steel. Sharper and easier to sharpen than stainless, and reactive: it develops a patina and will rust if left wet.

Patina — The stable gray-blue oxide layer that forms on carbon steel with use. Largely protective and entirely normal — not to be confused with red rust.

Edge retention — How long a blade keeps a keen edge under use. Driven mainly by hardness and carbide structure.

Toughness — Resistance to chipping and cracking. Inversely related to hardness — the central trade-off in Japanese versus German knives.

Sharpening

Bevel — The ground face that runs from the edge up the side of the blade. A double bevel is ground on both sides; a single bevel on one.

Included angle — The total angle at the apex — double the per-side angle. A 15° per side edge has a 30° included angle. Listings use both, which causes endless confusion.

Apex — The actual cutting line where the two bevels meet. A knife is sharp when the apex is narrow and clean.

Burr (wire edge) — The thin lip of displaced steel pushed to the far side when the bevels meet. Proof of sharpening; must be removed before the knife will cut properly. See why your knife won’t get sharp.

Micro-bevel — A very narrow secondary bevel at a slightly steeper angle, added in two or three light strokes. Strengthens the apex and makes future touch-ups faster.

Honing — Realigning a rolled edge with a rod. Removes essentially no metal and does not sharpen.

Stropping — Dragging the edge spine-first across leather (sometimes charged with fine compound) to remove the last of a burr and polish the apex.

Grit — The abrasive fineness of a stone. Roughly: 400 for repair, 1000 to sharpen, 3000–6000 to finish. See the grit guide.

Slurry — The milky suspension of loose abrasive and steel that forms on a wet soft stone. Part of the cutting mechanism, not mess.

Dishing — The hollow that wears into the middle of a stone. Causes a convex bevel and a drifting angle — fix it by flattening the stone.

Splash-and-go — A stone that needs only wetting rather than a soak. Hard ceramic stones are typically splash-and-go; soft water stones typically are not.

Reprofiling — Grinding a new, different bevel angle onto a knife. Removes a lot of metal and takes a long session — which is why matching the existing angle matters. See the angle guide.