Contents: Top - 0–9 A B C D E F G H I J K L M N O P Q R S T U V W X Y Z


Assault rifle

Assault rifles.

A selective fire rifle chambered for an intermediate cartridge, fed from a box magazine. Became the primary military rifle during the Vietnam War. It was pioneered by the Sturmgewehr 44, which was introduced during the conflict by the Third Reich.

Artificial Intelligence

A computer program that has reasoning abilities approaching that of humans. They can be used to control robots. The Patriots' AIs completely control human life.

Artificial Muscle

Synthetic tissue that can be used to simulate muscle and provide great amounts of strength. Commonly used in muscle suits and in the legs of some Metal Gear models.

Air Cushion

Hovercraft travel is enabled by creating a cushion of pressurized air beneath the vehicle that supports its weight. Only a small amount of force is then required to move it.


An ambush is a type of attack where one waits for their opponent to pass by. They can then be caught off guard and forced to surrender.

Active Denial System

A non-lethal directed-energy weapons system that is used for crowd control. It operates by firing a high-powered beam of electromagnetic radiation in the form of high-frequency millimeter waves at 95 GHz.


Battle Damage Assessment

Battle Damage Assessments, also known as Bomb Damage Assessments, is the practice of assessing damage inflicted by the target of an air raid.

Black Project

Secret projects paid for by the Pentagon's black budget. It avoids a lot of red tape, and apparently puts a huge amount of lead time in creating weapons projects. Also, because of black projects, no one could bother the people involved, not even the Military Oversight Committee.


An item that can be placed in the path of guards to distract them. It is implied to be a pornographic magazine.


Boss was a title given to America's greatest and most influential soldier. The Boss gained the title due to her achievements in the second World War, most notably on her participation in the D-Day Landings at Normandy (in which her son Ocelot was born). Naked Snake gained the title "Big Boss" after defeating The Boss, as a testament to the fact that he had surpassed her.

Brain Bombs

A technology that was developed in 1992, with the objective of using the electromagnetic spectrum to cause disorientation. Drago Pettrovich Madnar was instructed by Western politicians to develop them, but he instead opted to continue his work on Metal Gear.


An action where someone accepts an item (usually a large sum of cash) in exchange for looking the other way regarding something, mostly things that are illegal in nature.



Name used to keep an agent's identity a secret. They can often be changed from mission to mission so that it does not appear that the same person was involved in them.

For the gameplay unlockable for the various games in the Metal Gear series, see Codename (gameplay). For the character names, see Random Codenames.

Commanding Officer

A high-ranking military official who gives commands to his unit. Can also be considered a mentor of the unit. Most of the time is the leader of the unit.


Close Quarters Battle. Not to be confused with CQC (Close Quarters Combat) or MOUT (Military Operations in Urban Terrain). CQB is the discipline of assaulting, or "taking down" an enemy-held building room-by-room. CQB often involves hostage rescue. In CQB, the enemy is generally confined to a specific building or complex. Friendly forces generally have some intel concerning the building layout and number of enemy personnel. CQB is always a team exercise, and utilizes practiced room-clearing techniques in which each team member upon entry scans a specific area of the room and engages targets within that area. This may be done one room at a time or with multiple teams clearing multiple rooms simultaneously. Distraction devices (i.e. flashbangs), stun grenades, tear gas, frag grenades, and explosive breaching charges may be used in CQB, depending on the situation. In addition, there are two variants of CQB, unarmed CQB involving punches and kicks, and flip CQB where the practitioner, upon grabbing an attacking enemy, succeeds in flipping the enemy over and flat onto their back. The latter variant also knocks out the soldier instantaneously. Solid Snake, after giving up on CQC, mainly resorted to CQB as his main fighting style until Liquid Ocelot's Insurrection, of which Master Miller was implied to have taught him the basics of CQB.



Term used to describe someone who is using performance enhancing drugs, such as steroids. Often used to improve athletic performance.

Dot sight

A dot sight is a targeting system used on firearms. A red dot is on the scope lens to show where the bullets will hit.


A type of medicine. It is used to clean wounds to prevent bacteria or foreign entities from entering wounds prior to fixing up the wounds.


A remote-controlled vehicle used to perform guard duties or surveillance.


A move that is performed while the main character is running, it can be used to:

  • Knock over guards.
  • Cross gaps.
  • Silently move over grates.

Double agent

An agent that works for two intelligence agencies at the same time. Often they are recruited by an agency when they are found out. Their only option is to become a double agent. The agent then feeds them intel from the other agency while they give disinformation to the other.



Acronym for Explosive Ordinance Disposal. It is a bomb disposal unit sent in to defuse unexploded ordnance. An extremely high-risk job with a high mortality rate. EOD technicians are all volunteers.


Having an item or weapon equipped means that it is the current one selected for use.

Equipped Item

An equipped item can often work automatically. For instance rations will automatically restore health if the player's health is reduced to zero.

Equipped Weapon

An Equipped weapon used to take down enemies.


Extra-Sensory Perception. Often referred to as a psychic ability, someone with ESP has heightened senses, especially in terms of the mind. Some powerful users may also be able to utilize telepathy and to predict future events.

Extra Ops

Various operations conducted by the Militaires Sans Frontières which, while not immediately important to the main mission at hand, will help them nonetheless.



FAR is a research facility in the game Metal Gear Acid, in the northernmost part of the Plant where Dr. Flemming would command researchers. Only the doctor's research advisers were allowed into the place. It is an acronym for Flemming's Assembly Room.

Film Badge

An identification card that has a special film on it used to detect radiation. The device's proper name is "dosimeter." It is primarily used in areas where nuclear material is located. Also commonly called a radiation badge.

Fire Extinguisher

An active fire protection device that can spray a vapor that can extinguish fires. Shooting one of these will cause them to detonate into a mist, which can also be used to either expose infrared sensors or make a hasty getaway from enemies.


A slang term for the termination of employment, largely if the employee was given this fate did something his superiors did not approve of or due to needing to make room for newcomers.


Gun attachment used to identify targets in the dark. It is also useful for temporarily blinding opponents.

Foregrip A/B

A "Foregrip" is a handle put on the bottom rail of a long gun such as a Mk. 17 or an M4 Carbine. It serves as a more ergonomic way to hold the muzzle end of a firearm for quick target acquisition at close range, and also improves ability to control a weapon during automatic fire. However, use of this attachment tends to reduce accuracy at long ranges due to the shooter's tendency to attempt to adjust the front half of the rifle rather than resting it. An excellent attachment for short-range shooting, a detriment otherwise.


This was the codename given to the greatest soldier in FOXHOUND, Gray Fox. Roy Campbell was also awarded the title "Chicken Fox", as a joke because he was reluctant to do actual field combat and preferred to stay behind as a tactician. Solid Snake may have inherited the codename of Fox, after he defeated Gray Fox in Zanzibar Land.


A suitcase that contains the communications equipment and authentication codes required for the President of the United States to order the launch of a nuclear weapon. The Football is carried by a military aid and is kept at the President's side (or at least the next room) at all times. Also referred to as the briefcase, the red button, and sometimes the package.



Military slang for an inexperienced soldier.


A type of warfare. It is an unconventional form of warfare where soldiers resort to ambushes and raids on larger, less mobile armies.

Gun Launderer

Gun launderers are people who make a living "laundering" (i.e., illegally supplying unregistered people with) guns. To do this, they often make "naked guns", as in, they strip the gun of ID chips so that anyone can use the weapon. Even though they are supposed to be illegal, Drebin implies at one point that the Patriots deliberately allowed them to exist.



A handheld weapon that is easily concealable and mobile. For example, the M1911A1 is considered a handgun.


High Altitude-Low Opening - a method of parachuting where the paratrooper skydives to a low altitude before deploying their parachute. The first HALO jump was performed by Naked Snake in 1964 just prior to the commencing of the Virtuous Mission.


High Altitude-High Opening - a method of parachuting where the paratrooper skydives and then deploys their parachutes at the same altitude.


A place where a particular set of rules do not apply.


When the main character is hanging onto a ledge he can drop and grab the next ledge down. This requires very good timing to pull off.

Hold up

A type of ambush where the attacker aims a gun at the target before they can get their own gun out. The target is then forced to surrender as they would be shot otherwise. The use of the word "Freeze!" when holding someone up is not uncommon. This is often used to gain extra equipment from guards. Snake can leave with the guard still standing there as long as he does not see Snake leave. Guns without ammo can also be used for a hold up. There are three methods where a soldier can be held up. One of which is for them to hold up both hands in surrender, and, if the person holding them up has his/her gun pointed at the held-up soldier is held up, the soldier will beg for mercy and then shake his/her body to let loose any equipment of his/hers. The second method is, if the soldier is on the ground, the soldier places his/her hands on his head, and if pointing a gun at his/her head, they'll shake his/her hips to let go of any equipment belonging to them. The third method is to for the soldier to, if standing, freeze up in shock, and get down onto the ground to put his/her hands on his/her head.



Inter-Continental Ballistic Missile. Missile that when fired from the US could reach Russia (and vice versa). When armed with nuclear weapons they contribute to MAD.


Intermediate Range Ballistic Missile. Missiles has the range to hit targets within the same continent.


Russian/Slavic Christian name equivalent to the English "John." Proper Russian pronunciation is "EE-Vahn," though non-Russian speakers generally pronounce it "Eye-Ven." In the West, the primary use of "Ivan" is a generic term (and sometimes ethnic slur) towards Russians or people of Russian descent (it derives from famous 17th-Century Czar Ivan Romanov, better known as Ivan the Terrible).


La Li Lu Le Lo

Codename for the Patriots. By the time of the Tanker Incident, nanomachines had become widely available and the Patriots were able to use them to censor out their name, replacing it with the phrase "La-Li-Lu-Le-Lo." During Operation Snake Eater, Snake was given the passphrase "Who are the Patriots?" to identify ADAM with by Major Zero, to which the answer was "La-Li-Lu-Le-Lo."

Laser sight

a firearm attachment that projects a laser beam onto targets. It's useful for targeting when not in first person.

Lucinda File

Lobito Incident



A device used to covertly hide data as the data is written microscopically.

Militia Squad Leader

Military instructors brought in from the PMCs. They also fight alongside the militia. In the Middle East, Snake wears the same cloak that they do.

Meat wagon

Slang term for an ambulance, more specifically the kind that retrieves recently-deceased or recently-discovered deceased individuals.

Mutually Assured Destruction

Mutually Assured Destruction is when the threat of destruction from a follow-up nuclear strike prevents an aggressor from using their nuclear weapons. The long flight time and ease of detection of an IBCM means that an opponent is able to detect a first strike and respond before they are destroyed.


Acronym for "Material Unaccounted For." It is usually used in reference to nuclear material that has not been disposed of at all, and is being distributed via a black market.

Major Zero/Major Tom

For the Virtuous Mission, Naked Snake's commanding officer, Major Zero, chose to use the Codename "Major Tom", as he thought Tom was the name of the tunnel used to escape in The Great Escape. However, after the mission the Major discovered that the tunnel was one of the ones that was discovered. He therefore decided to change his codename back to Zero.



North Atlantic Treaty Organization. Military alliance of North American and Western European countries, originally formed to ensure common defense against aggression by Stalin's Soviet Union..


The practice of going into a battlefield without weapons or equipment. Big Boss received his Naked Snake codename because of this practice. See also on-site procurement.

Naked Gun

Gun that does not have an ID chip as it was either developed before the SOP system or it had it's ID chip removed by certain gun vendors. Because of this it is undetectable by the system and can be used by anyone. Also the title of a trilogy of slapstick comedy movies starring Leslie Nielsen (as Frank Drebin) and George Kennedy.

Naked Nuke

See Naked Gun. Since such a nuke is not on the SOP system the Patriots will not see it coming if it is used against them.

Naked Vehicles

See Naked Gun and Naked Nuke. A vehicle that is not on the SOP system. It can range from land based transportation vehicles to aerial aircraft, to even naval vessels.



Ocelot used variations of his name over the years: "Major Ocelot", "Revolver Ocelot", and "Liquid Ocelot." The name was also used by Ocelot's soldiers: the Ocelot Unit. The name is derived from a small cat in South/Central America that resembles a mixture between a house cat and a leopard.

Oil fence

A floating structure surrounding the Big Shell intended to prevent oil from escaping to the surrounding area.

On-Site Procurement

This protocol is followed when an operative does not bring his or her own weapons and equipment on a mission, to prevent them from being connected with the country that sent them.

Outer Ops

Turn based game in Metal Gear Solid: Peace Walker. According to Kazuhira Miller, the premise is that the MSF troops are dispatched to various hotspots around the world to give out aid in battle. If they participate, and survive the battle, they'll gain a lot of GMP for their troops, as well as new equipment and supplies, more experience, and even possibly recruit a few members, although it does come at the risk of soldiers injuring themselves or even dying in battle.



The ability to move objects or even people with the mind alone. Also known as telekinesis.


Another word for a grenade. Comes from the iconic pineapple-like shape of the American Mk2 grenade.



Exploration to gather useful intel. Usually carried out stealthily.


The reaction force from a gun firing. Recoil causes the weapon to push backwards into the shooter's hand/shoulder while simultaneously forcing the muzzle upwards. The amount of felt recoil depends on the operating pressure of the round being fired (not the actual terminal energy of the bullet; contrary to popular belief, the more powerful .45 caliber M1911 has less felt recoil than the weaker 9mm M9, because 9x19mm operates at higher pressure than .45ACP despite its inferior terminal ballistics) and the weight of the weapon itself (heavier gun equals less felt recoil), as well as the type of weapon (automatics use either recoil energy or expanding gas pressure to cycle the weapon, and thus kick less than revolvers or bolt-actions). Muzzle climb is affected by the height of the barrel axis above the grip (higher barrel axis equals more muzzle climb) and rate of fire (shoot faster, get more muzzle climb). Many automatic weapons have a compensator (also called a muzzle brake) mounted to the muzzle of the weapon, which directs propellant gas upwards to partially counter the effect of muzzle climb.

Rocket stage

Large rockets are usually made up of multiple sections. Once the fuel in a stage is used up it can be jettisoned making the rocket lighter.


Military slang for an inexperienced soldier. A less polite and equally common term is FNG (Fucking New Guy).

Russian Roulette

A lethal game of chance originating in Russia where the player will use a revolver with a single loaded bullet in it to see if the bullet would fire on the other player or even the player who loaded it. Revolver Ocelot played a variation using three models of the Single Action Army revolver, with only one gun having a bullet inside the chamber, and juggles them to intimidate his opponents, having done so with Nikolai Stephanovich Sokolov and Tatyana/EVA.



A type of device on sniping rifles. It's often used to magnify a target that is a large distance from the sniper.


Device sometimes attached to the muzzle of a firearm that reduces the amount of sound a gunshot makes as well as reducing muzzle flash. Often incorrectly called a "silencer" in popular culture.

START 3 Treaty

The START III Treaty was a treaty that was intended to be made between Russia and the USA to limit the stockpile of nuclear missiles down to 2000.


Short Take Off and Landing. For aircraft capable of a vertical take-off a short take-off is often preferable. Making a short takeoff is more efficient than a vertical one as it allows the aircraft to carry more weight (fuel and weapons).

Super Baby Method

A technology for intensifying fetus growth in the womb. A fertilized egg created using a cell nucleus is divided and eight cloned babies are transferred to a womb. Then, by intentionally weeding out and eliminating six cloned babies at a specific point in time, the growth potential of the remaining two cloned babies is increased.

Support Team

A team of experts that an agent can communicate with to get advice from.


A slang term for members of the United States Federal Government and its various branches.

Special Forces

Special units of elite soldiers trained to do special tasks that are not required of normal soldiers.

Sneaking Mission

A sneaking mission is one where a heavily fortified area is infiltrated by a single soldier. The soldier then has to prevent the enemy from discovering their presence. It is to be noted that it is mandatory for a single soldier to participate in a sneaking mission for it to be a sneaking mission, although multiple soldiers sneaking in one at a time is also possible and allowed for.[1]


Naked Snake was given his codename as a reference to The Boss's Cobra Unit, as well as a reference to the fact that he, due to the policies of on-site procurement, does not have any equipment on him, making him essentially "naked."

Solid Snake and Liquid Snake were given their names as a reference to their father, Naked Snake, and as a reference to the fact that they were opposites of one another. Solidus Snake was given his code name due to him being a perfect clone of Big Boss (Solidus being the point when a substance is neither solid nor liquid).

Raiden was given the title Snake briefly by the Patriots as they were trying to fashion him into the next Solid Snake (see S3 Plan for more details).


A person highly skilled in the art of tracking.


Missile fired from the ground at an aircraft in flight


Specially-trained soldier who uses a precision rifle to engage specific targets at long range. In addition to being highly-skilled marksmen, snipers are trained in infiltration, camouflage, scouting, and survival. Snipers will often remain in their firing/observation position for days, sometimes with enemy troops literally right on top of them, without being detected. After taking the shot, the sniper team will relocate to a new position using a pre-planned escape route. Snipers usually work in teams of two: the shooter uses the long-range rifle, while the spotter observes through high-powered optics to call out ballistic corrections and prioritize targets.

Sniper rifle

A specialized rifle used to shoot at targets from far away.


A smoothbore firearm designed primarily to fire shotshells containing multiple lead pellets. Upon leaving the barrel, these projectiles spread out into a conical pattern, widening as they fly farther from the weapon. The exact rate of dispersal varies depending on the shotgun's barrel length and choke. These pellets, called shot, range from tiny #10 birdshot for fowling to big 00 (pronounced "double-ought") buckshot for large game or combat use. Combat shotguns tend to have short- to medium-length barrels with little or no choke, allowing them to also fire slugs (very large single projectiles) as well as a variety of less-lethal munitions (beanbags, V-ring rounds, etc.). Shotguns excel in short-range combat, but lose effectiveness at longer ranges, generally becoming completely useless beyond 50 yards.


Slang term for nuclear warheads.


Soldier who helps a sniper pick targets and looks out for threats.


Theatre Missile Defense

A missile defense system that defends an area or vehicle from theatre-range ballistic missiles (i.e., missiles with a range between 300 km to 3500 km).

Triple agent

A spy who belongs to three different organizations and passes on pertinent information on all of them.



An Unmanned Combat Aerial Vehicle is a type of aircraft that is either remotely operated or AI controlled. It has its own weapons systems allowing it to attack targets as it sees them.


Not having an item or weapon equipped. Since only one menu item can be selected at a time most of them will be unequipped. Tapping the equip button allows you to unequip rapidly which is useful if you need both hands (for instance, when dragging a body).


Volley Gun

Gun that has multiple barrels. The barrels can fire all at once or one after another.


Vertical Take Off and Landing. An aircraft designed to take-off without needing a runway.


Wind Barrier

A security system installed on the top of Building 1, in the fortress of Outer Heaven, which prevents intruders from accessing the roof. It can only be bypassed with the use of a bomb blast suit.

Wing in Ground effect

An aircraft at low altitude experiences an effect caused by its wings pressurizing the air against the ground (like an air cushion). This provides a small amount of additional lift to that provided by the wings.


Short for Women's Army Corps. The WAC program was instituted in 1942, placing female volunteers in non-combat auxiliary roles Stateside and in major theater bases abroad, thereby freeing up more manpower for combat. Similar programs included the U.S. Navy WAVEs and Army Air Force WASPs.



A term that dates back to around the 1770s. It is often used in reference to Americans (usually as an insult).


Zero Shift

The ability to teleport. Teleportation was initially thought to be a pipe dream reserved for futuristic mobile weapons. But Gene, with his impressive ESP abilities, was able to master it.

Notes and References

  1. ^ Portable Ops: Jonathan: Big Boss, let's go over how to switch team members. You won't be sneaking in alone, anymore. We'll all be sneaking in together.
    Naked Snake: I thought going in alone was the whole point of a Sneaking Mission.
    Jonathan: Right, I know. Going in all at once wouldn't be very bright. We'll move in one at a time, and switch off as we go along.
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