A cleaver is a large knife

Knife

A knife is a cutting tool with an exposed cutting edge or blade, hand-held or otherwise, with or without a handle. Knives were used at least two-and-a-half million years ago, as evidenced by the Oldowan tools...

 that varies in its shape but usually resembles a rectangular-bladed hatchet

Hatchet

A hatchet is a single-handed striking tool with a sharp blade used to cut and split wood...

. It is used mostly for hacking through bones as a kitchen knife

Kitchen knife

A kitchen knife is any knife that is intended to be used in food preparation. While much of this work can be accomplished with a few general-purpose knives – notably a large chef's knife, a tough cleaver, and a small paring knife – there are also many specialized knives that are designed for...

 or butcher knife

Butcher knife

A butcher knife is a knife designed and used primarily for the butchering and/or dressing of animals.During the late 18th century to mid 1840s, the butcher knife was a key tool for mountain men. Simple, useful and cheap to produce, they were used for everything from skinning beaver, cutting food,...

, and can also be used for crushing via its broad side, typically garlic.

Design

In contrast to other kitchen knives, the cleaver has an especially tough

Toughness

In materials science and metallurgy, toughness is the ability of a material to absorb energy and plastically deform without fracturing; Material toughness is defined as the amount of energy per volume that a material can absorb before rupturing...

 edge meant to withstand repeated blows directly into thick meat and dense cartilage and even bone, not to mention the cutting board or other supporting surface below. This resilience is accomplished by using a softer steel and a thicker blade, because a harder steel and a thinner blade will fracture more readily. Formally, weaker knives would suffer buckling

Buckling

In science, buckling is a mathematical instability, leading to a failure mode.Theoretically, buckling is caused by a bifurcation in the solution to the equations of static equilibrium...

 failure when used in a cleaving fashion.

And in contrast to all other kitchen tools but one, a meat tenderizer, it is the only one designed to be swung like a hammer.

The edge of a meat cleaver does not need to be particularly sharp, because the knife's design, like that of a hatchet or an axe, relies on sheer momentum to cut efficiently, to slash straight through rather than slicing in a sawing motion. Part of the momentum derives from how hard you swing, of course, and the other part derives from how heavy the cleaver is.

A knife-sharp edge on a cleaver is undesirable because it would quickly become more blunt than it if were less sharp but sturdier to begin with. The grind

Grind

The grind of a blade refers to the shape of the cross-section of the blade. It is distinct from the type of blade , though different tools and blades may have lent their name to a particular grind.Grinding involves removing significant portions of metal from the blade and is thus distinct from...

 of Eastern Asian kitchen knives is 15–18 degrees, and for most Western kitchen knives it is 20–22°. But for a meat cleaver it is even blunter, more like 25°.

The tough metal and thick blade of a cleaver also make it a suitable tool for crushing with the side of the blade. This contrasts with certain hard, thin slicing knives, which should not be used for crushing because they can crack under such repeated stress.

Use

Cleavers are primarily used for cutting through thin or soft bones and sinew, or through hard vegetables such as squash, where twisting may chip or shatter a slicing blade. For example, a cleaver is well-suited to cutting apart a chicken, which has thin bones, or separating ribs.

Cleavers are not used for cutting through thick, hard bones – instead, one employs a bone saw, either manual or powered.

Cultural references

Cleavers occur with some frequency in traditional Chinese thought.

An old Zen

Zen

Zen is a school of Mahāyāna Buddhism founded by the Buddhist monk Bodhidharma. The word Zen is from the Japanese pronunciation of the Chinese word Chán , which in turn is derived from the Sanskrit word dhyāna, which can be approximately translated as "meditation" or "meditative state."Zen...

 story on the proper use of a cleaver tells of a butcher who effortlessly cut ox carcasses apart, without ever needing to sharpen his cleaver. When asked how he did so, he replied that he did not cut through the bones, but rather in the space between the bones.

In explaining his ideal of junzi

Junzi

Junzi or nobleman, was a term used by Confucius , to describe his ideal human. To Confucius, the functions of government and social stratification were facts of life to be sustained by ethical values; thus his ideal human was the junzi...

, Kǒng Fūzǐ remarked "Why use an ox-cleaver to carve a chicken?" on the futility of the common people seeking to emulate noblemen.

Norwegian Bard Fossen uses the term 'Cleaver' in his official title "The Immortal Sir. F. Bard 'The Cleaver' Fossen III Esq." .

Japan

In Japanese cutlery, the main cleaver used is the light-duty deba bocho

Deba bocho

Deba bocho are Japanese style kitchen carvers used to cut fish, as well as chicken and meat. They come in different sizes, sometimes up to 30 cm in length. The deba bocho first appeared during the Edo period in Sakai. It is designed to behead and fillet fish...

, primarily for cutting the head off fish (fish are the main meat in traditional Japanese cuisine).

For crushing vegetables, a shamoji

Shamoji

A shamoji is a flat rice paddle used in Japanese cuisine. It is used to stir and to serve rice, and to mix vinegar into the rice for sushi....

 (rice paddle) is used instead of the thin knives generally used in Japanese kitchens.

Chinese "cleaver"

The Chinese chef's knife is frequently incorrectly referred to as a Chinese "cleaver" due to the similar rectangular shape. Although the Chinese chef's knife looks much like the cleavers familiar in butcher shops in Europe and North America, Chinese chef knives are much thinner in cross-section and are intended more as general-purpose kitchen knives, as a chef's knife

Chef's knife

In cooking, a chef's knife, also known as a French knife or a cook's knife, is a cutting tool used in food preparation. The chef's knife was originally designed primarily to slice and disjoint large cuts of beef...

. A Chinese chef's knife is mostly used to slice boneless meats, chop, slice, or mince vegetables, and to flatten garlic bulbs or ginger, while also serving as a spatula to carry prepared ingredients to the wok.

For butchering tasks and to prepare boned meats, the Chinese have long produced a heavier series of 'bone' cleavers designed to take care of tasks similar to the Western meat cleaver.