A deadly weapon, sometimes dangerous weapon, is a statutory definition

Statute

A statute is a formal written enactment of a legislative authority that governs a state, city, or county. Typically, statutes command or prohibit something, or declare policy. The word is often used to distinguish law made by legislative bodies from case law, decided by courts, and regulations...

 listing certain items which can inflict mortal or great bodily harm. In addition, deadly weapon statutes often contain "catch all" provisions which describe abilities used to designate other implements as deadly weapons.

Whether an item can actually inflict such harm often does not affect the designation. For example, an unloaded gun

Gun

A gun is a muzzle or breech-loaded projectile-firing weapon. There are various definitions depending on the nation and branch of service. A "gun" may be distinguished from other firearms in being a crew-served weapon such as a howitzer or mortar, as opposed to a small arm like a rifle or pistol,...

 or a gun with a trigger lock

Trigger lock

A trigger lock is a device designed to prevent a firearm from being discharged while the device is in place. Generally, two pieces come together from either side behind the trigger and are locked in place, which can be unlocked with a key or combination. This physically prevents the trigger from...

 are often treated like any other firearm.

Examples of deadly weapons

A deadly weapon is usually defined as a firearm

Firearm

A firearm is a weapon that launches one, or many, projectile at high velocity through confined burning of a propellant. This subsonic burning process is technically known as deflagration, as opposed to supersonic combustion known as a detonation. In older firearms, the propellant was typically...

 or any object designed, made, or adapted for the purposes of inflicting death or serious physical injury. In addition to all firearms, the term deadly weapon encompasses knives

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...

 of a certain length (usually three inches or longer, depending on jurisdiction), and in almost all jurisdictions includes the switchblade

Switchblade

A switchblade is a type of knife with a folding or sliding blade contained in the handle which is opened automatically by a spring when a button, lever, or switch on the handle or bolster is activated A switchblade (also known as an automatic knife, pushbutton knife, switch, Sprenger, Springer,...

, gravity knife

Gravity knife

A gravity knife is a knife with a blade contained in its handle, and which opens its blade by the force of inertia or gravity. As the gravity knife requires gravity or inertia to propel the blade out of the handle, it differs fundamentally from the switchblade, which opens its spring-propelled...

, ballistic knife

Ballistic knife

A ballistic knife is a specialized combat knife with a detachable gas- or spring-propelled blade that can be fired to a distance of several feet or meters by pressing a trigger or switch on the handle.-History and usage:...

, stiletto

Stiletto

A stiletto is a knife or dagger with a long slender blade and needle-like point, intended primarily as a stabbing weapon. The stiletto blade's narrow cross-section and acuminated tip reduces friction upon entry, allowing the blade to penetrate deeply...

, ice pick, sword

Sword

A sword is a bladed weapon used primarily for cutting or thrusting. The precise definition of the term varies with the historical epoch or the geographical region under consideration...

, dagger

Dagger

A dagger is a fighting knife with a sharp point designed or capable of being used as a thrusting or stabbing weapon. The design dates to human prehistory, and daggers have been used throughout human experience to the modern day in close combat confrontations...

, billy club, blackjack, bludgeon

Club (weapon)

A club is among the simplest of all weapons. A club is essentially a short staff, or stick, usually made of wood, and wielded as a weapon since prehistoric times....

, brass knuckles

Brass knuckles

Brass knuckles, also sometimes called knuckles, knucks, brass knucks, or knuckledusters, are weapons used in hand-to-hand combat. Brass knuckles are pieces of metal, usually steel despite their name, shaped to fit around the knuckles...

, nunchaku

Nunchaku

is a traditional Okinawan weapon consisting of two sticks connected at their ends with a short chain or rope.-Etymology:The Japanese word nunchaku is the Kun'yomi reading of the Kanji term for a traditional Chinese two section staff....

 (fighting sticks), shuriken

Shuriken

A shuriken is a traditional Japanese concealed weapon that was generally used for throwing, and sometimes stabbing or slashing...

 (throwing stars), among other weapons.

In some jurisdictions, a distinction is made between deadly weapons and destructive device

Destructive device

In the United States, a destructive device is a firearm or explosive device regulated by the National Firearms Act of 1934.Examples of destructive devices include grenades, and firearms with a bore over one half of an inch, including some semi-automatic shotguns. While current federal laws allow...

s, such as explosives, incendiary

Incendiary ammunition

-World War I:One of the first uses of incendiary ammunition occurred in World War I. At the time, phosphorus—the primary ingredient in the incendiary charge—ignited upon firing, leaving a trail of blue smoke. They were also known as 'smoke tracer' for this reason. The effective range of...

 or poison gas bomb

Bomb

A bomb is any of a range of explosive weapons that only rely on the exothermic reaction of an explosive material to provide an extremely sudden and violent release of energy...

s, grenade

Grenade

A grenade is a small explosive device that is projected a safe distance away by its user. Soldiers called grenadiers specialize in the use of grenades. The term hand grenade refers any grenade designed to be hand thrown. Grenade Launchers are firearms designed to fire explosive projectile grenades...

s, landmines

Land mine

A land mine is usually a weight-triggered explosive device which is intended to damage a target—either human or inanimate—by means of a blast and/or fragment impact....

, rocket

Rocket

A rocket is a missile, spacecraft, aircraft or other vehicle which obtains thrust from a rocket engine. In all rockets, the exhaust is formed entirely from propellants carried within the rocket before use. Rocket engines work by action and reaction...

s, missile

Missile

Though a missile may be any thrown or launched object, it colloquially almost always refers to a self-propelled guided weapon system.-Etymology:The word missile comes from the Latin verb mittere, meaning "to send"...

s, or similar devices, including the unassembled components from which such devices can be made.

In 19th century France, a closed fist was considered a deadly weapon and thus combatants would kick or strike each other with an open-palmed slap, possibly influencing the French martial art Savate

Savate

Savate , also known as boxe française, French boxing, French kickboxing or French footfighting, is a French martial art which uses the hands and feet as weapons combining elements of western boxing with graceful kicking techniques. Only foot kicks are allowed unlike some systems such as Muay...

.

In Wisconsin

In Wisconsin

Wisconsin

Wisconsin is a U.S. state located in the north-central United States and is part of the Midwest. It is bordered by Minnesota to the west, Iowa to the southwest, Illinois to the south, Lake Michigan to the east, Michigan to the northeast, and Lake Superior to the north. Wisconsin's capital is...

, statute §939.22(10) defines dangerous weapon:

"Dangerous weapon" means any firearm, whether loaded or unloaded; any device designed as a weapon and capable of producing death or great bodily harm; any electric weapon, as defined in s. 941.295 (4); or any other device or instrumentality which, in the manner it is used or intended to be used, is calculated or likely to produce death or great bodily harm.

In Pennsylvania

Title 18 Pa.C.S.A 2301 "Deadly Weapon"

Any firearm, whether loaded or unloaded, or any device designed as a weapon and capable of producing death or serious bodily injury, or any other device or instrumentality which, in the manner in which it is used or intended to be used, is calculated or likely to produce death or serious bodily injury.

Penalty enhancer

The use or possession of a deadly weapon during the commission of a crime often constitutes a penalty

Sentence (law)

In law, a sentence forms the final explicit act of a judge-ruled process, and also the symbolic principal act connected to his function. The sentence can generally involve a decree of imprisonment, a fine and/or other punishments against a defendant convicted of a crime...

enhancer. The deadly weapon penalty enhancer is premised on a belief that commission of the particular crime is inherently more dangerous.