Air Force: A military organization that primarily operates in aerial warfare. It is one of the five uniformed military branches.

Alaskan Scouts: Alaska Army National Guard's 207th Infantry Group, renowned as Alaska's "arctic warriors."

Aleutians: A native or inhabitant of the Aleutian Islands, a group of volcanic islands of southwest Alaska.

Angel of Death: Another name for the Grim Reaper, a fictional character which has existed in mythology and popular culture since the earliest days of storytelling.

Apoptosis: Disintegration of cells into membrane-bound particles that are then eliminated by the engulfing and ingestion of bacteria or by shedding.

ArmsTech: A military weapons manufacturing company, and the co-developing company of Metal Gear Rex.

Asymmetry Theory: The theory that a species shows signs of symmetry before it becomes extinct.

ATGC Inc: Adenine, Thiamine, Guanine and Cytosine, a leading company in the field of bioengineering. Along with the Department of Defense, it was they who started the gene therapy project.

AWACS: Airborne Warning and Control System, a military surveillance system carried by aircraft, which is capable of tracking a large number of other aircraft over a vast distance.

B2 Spirits: A multi-role heavy bomber that travels at high subsonic speed. Can carry conventional or nuclear arms.

BDA: Battle Damage Assessment, the timely and accurate estimate of damage resulting from the application of military force, either lethal or non-lethal, against a predetermined objective.

Benzedrine: A trademark formerly used for a preparation of amphetamine, a colorless, volatile liquid used as a central nervous system stimulant in the treatment of certain conditions, such as attention deficit hyperactivity disorder and depression.

Bering Sea: A northward extension of the Pacific Ocean between Siberia and Alaska, lying north of the Aleutian Islands and connected with the Arctic Ocean by the Bering Strait.

Big Boss: An extraordinary man who was known as the greatest living soldier in the world. He was responsible for the Outer Heaven and Zanzibar incidents, and it was he who created FOXHOUND. His remains have been preserved by the military as a genetic sample of the greatest soldier that ever lived.

Black Project: A top-secret military/defense project, unacknowledged by the government, military personnel, and defense contractors.

Caribou: Any of several large reindeer native to northern North America.

Chernobyl: A city of north-central Ukraine near the border of Belarus. It was evacuated and remains uninhabited as a result of a major nuclear power plant accident nearby on April 26, 1986.

COA: Course of Action.

Codec: A two-way nano-tech radio invented by Mei Ling. Because it stimulates the small bones of the ear, only the wearer of the codec is able to hear what is being said through the codec.

Constitution: A written document executed by representatives of the people of the United States as the absolute rule of action and decision for all branches and officers of the government.

CTBT: Comprehensive Test Ban Treaty, a treaty abolishing all forms of nuclear testing including underground nuclear tests.

Cyborg: A human who has certain physiological processes aided or controlled by mechanical or electronic devices.

Cytokine: A protein produced by cells of the immune system that help boost immune function.

DARPA: Defense Advanced Research Projects Agency, a government agency charged with the mission of researching various technologies for use in military applications.

Deepthroat: A reference to the anonymous informer who assisted reporters in their investigation into the Watergate scandal. Because of the scandal, Richard Nixon resigned as President and several White House aides ended up serving prison terms.

DIA: Defense Intelligence Agency, a major producer and manager of intelligence for the United States Department of Defense.

DNA: Deoxyribonucleic acid, a nucleic acid that carries the genetic information in the cell.

Ear Pull: An event of the World Eskimo-Indian Olympics in which two opponents pull each others' ears while enduring the harsh cold. It tests spiritual as well as physical strength.

Edgar Hoover: The Director of the FBI from 1924-1972. He was a vigorous anti-communist, and also a well-known racist.

Exoskeleton: An artificially externally equipped skeleton designed to raise the wearer's fighting abilities as high as possible.

F117: The world's first operational aircraft designed to use stealth technology, flown only by the United States Air Force.

F-16: A multirole fighting jet with speeds up to 1500 mph. Thought to be the backbone of the United States Air Force; it is used in air-to-air combat and air-to-surface attacks.

FBI: Federal Bureau of Investigation, the principal investigative unit of the US Department of Justice.

Five-five-sixer: An assault rifle that fires 5.56mm rounds.

FOXDIE: A retrovirus genetically modified to attack a specific person or peoples by identifying their DNA. The result is an apparent heart attack.

FOXHOUND: A Special Forces unit formed to deal with local insurgencies, regional conflicts and counter-terrorism. It was originally established by Big Boss.

Galena: A city of extreme northwest Illinois west-northwest of Rockford.

Gene Therapy: The process by which a person's genomic information is analyzed and a copy of the useful genes is inserted into a subject cell. This project was used to create Genome Soldiers with strong battle skills.

General Ivan: An alias referring to Revolver Ocelot.

Genome Soldiers: Soldiers created from the gene therapy project. These soldiers became the Next Generation Special Forces.

GPS: Global Positioning System, a system of satellites, computers, and receivers that is able to determine the latitude and longitude of a receiver on Earth by calculating the time difference for signals from different satellites to reach the receiver.

GRU: Glavnoe Razvedyvatel'noe Upravlenie, the secret service of the Soviet army.

Guerrilla: A member of an irregular, usually indigenous military or paramilitary unit operating in small bands in occupied territory to harass and undermine the enemy, as by surprise raids.

Gulf War Babies: Children who were born to Gulf War veterans.

Gulf War Syndrome: A medical condition affecting some veterans of the Gulf War, characterized by fatigue, headache, joint pain, skin rashes, nausea, dizziness, and respiratory disorders, and attributed to reactions to depleted uranium used in anti-tank rounds.

Gulf War: A war fought in 1991 in which a coalition of countries led by the United States destroyed much of the military capability of Iraq and drove the Iraqi army out of Kuwait.

Hind D: A variant of the Mil Mi-24, a large combat helicopter gunship and low-capacity troop transport operated from 1976 by the Soviet Air Force, its successors, and over thirty other nations. It is sometimes nicknamed "crocodile" due to its camouflage and hull shape.

Hiroshima Bomb: The first nuclear bomb dropped on a populated area on August 6, 1945. The city was almost completely destroyed by the blast.

Human Genome Project: A bioinformatics project that has identified the 30,000 genes in human DNA. The purpose is to store DNA sequence derived from these analyses in databases for use in biomedical research.

Imperialism: The policy of extending a nation's authority by territorial acquisition or by the establishment of economic and political hegemony over other nations.

Inuit: A member of a group of Eskimoan peoples inhabiting the Arctic from northern Alaska eastward to eastern Greenland, particularly those of Canada.

Japanimation: A style of animation developed in Japan, characterized by stylized colorful art, futuristic settings, violence, and sex.

Kasack: A member of a people of southern European Russia and adjacent parts of Asia, noted as cavalrymen especially during czarist times.

KGB: Komitet Gosudarstvennoy Bezopasnosti, the Committee for State Security, the Soviet foreign intelligence and security service.

Kurd: A member of a pastoral and agricultural people inhabiting the transnational region of Kurdistan in southwest Asia.

Les enfant terribles: A project commencing in 1972, in which Big Boss was cloned in order to create genetically perfected soldiers. Solid Snake and Liquid Snake were both results of the project.

Mafia: A secret criminal organization operating in the United States and engaged in illegal activities such as gambling, drug-dealing, and prostitution.

Manhattan Project: The project concerning the development of the atomic bomb.

Metal Gear Rex: The name of the new Metal Gear prototype. It is a nuclear-equipped walking battle tank, and an enormous threat to the world.

MUF: Material Unaccounted For.

Mujahideen: Muslim guerrilla warriors engaged in a jihad (Muslim holy war or spiritual struggle against infidels).

Muktuk Eating Contest: An event of the World Eskimo-Indian Olympics in which contestants must eat as much muktuk (whale skin and blubber) as they can as quickly as possible.

Musher: One who travels over snow on dogsleds.

Nanomachines: Tiny machines created by means of MEMS (MicroElectro Mechanical System) technology. Solid Snake's Nanomachines consist of a transmitter, radar and anti-NBC (Nuclear Biological and Chemistry) defense systems.

Next Generation Special Forces: Reserve members of FOXHOUND selected after undergoing genetic map testing. They originally had no battle experience, although after undergoing extensive gene therapy, they became highly capable soldiers.

NIF: National Ignition Facility. An ultra-high power laser research device currently under construction at the Lawrence Livermore National Laboratory, in Livermore, California.

NOVA: A proposed physics experiment designed to detect neutrinos sent from Fermilab

NPT: Non Proliferation Treaty, a treaty designed to prevent the spread of nuclear weapons to countries other than the "Big 5" (that is, the US, Russia, Great Britain, France and China). In practice, it had little effect.

NSA: National Security Agency, an agency responsible for encoding and decoding communications intelligence and protesting US signals and information systems.

Ohio Class Nuclear Submarine Discovery: The submarine that escorted Solid Snake to Shadow Moses Island via an SDV in Alaska's Bering Sea.

OSP: On-Site Procurement.

Otacon: An acronym for "Otaku Convention."

Otaku: A fan of Japanimation.

Outer Heaven: A heavily fortified nation formed deep in South Africa in the late 1980's that was actually a large-scale mercenary dispatchment company created by Big Boss. It was destroyed by Solid Snake in 1995.

PAL: Permissive Action Link. A safety control system built into all nuclear missiles and warheads. It is impossible to launch or lock a nuclear missile without using the PAL.

PAN: Personal Area Network, a computer network used for communication among computer devices close to one person. The reach of a PAN is typically a few meters.

Pentagon: A department of the federal executive entrusted with formulating military policies and maintaining American military forces.

Perestroika: The restructuring of the Soviet economy and bureaucracy that began in the mid 1980's.

Pineapple: Nickname for a hand-grenade.

POW: Prisoner of War.

Rail gun: A weapon, consisting mainly of conducting metal rails, that uses electromagnetic force to accelerate a projectile to a much greater speed than that achieved by conventional chemical propellant weapons.

Red tape: The collection or sequence of forms and procedures required to gain bureaucratic approval for something, especially when oppressively complex and time-consuming.

Rhodesia: The former name of modern Zimbabwe.

Rivermore National Labs: A company that, along with ArmsTech, created the new Metal Gear prototype, Metal Gear Rex.

Saladin: A reference to the Kurdish general who conquered Egypt and Syria in the twelfth century. Sniper Wolf used this name out of respect for Big Boss.

SCNT: Sub Critical Nuclear Testing.

SDI: Strategic Defense Initiative, a system proposed by US President Ronald Reagan on March 23, 1983, to use space-based systems to protect the United States from attack by strategic nuclear missiles.

SDV: Swimmer Delivery Vehicle, a manned submersible used to deliver United States Navy SEALs and their equipment for special operations missions.

Secretary of Defense: The top official of the Pentagon.

Selfish Gene Theory: A theory that holds that natural selection acts through differential survival of genes, increasing the frequency of those alleles whose phenotypic effects successfully promotes its own replication at the expense of their less efficient competitors.

Shadow Moses Island: An island off the coast of Alaska that is home to a Nuclear Weapons Disposal Facility.

Shaman: A member of certain tribal societies who acts as a medium between the visible world and an invisible spirit world and who practices magic or sorcery for purposes of healing, divination, and control over natural events.

Shape memory alloy: A material that changes shape at different temperatures.

Sioux people: A group of Native American peoples inhabiting the northern Great Plains from Minnesota to eastern Montana and from southern Saskatchewan to Nebraska.

Sneaking Suit: The suit Snake wears throughout his mission at Shadow Moses. Created by Naomi Hunter, it is designed to prevent hypothermia and protect vital organs from harm.

Soliton radar: State-of-the-art radar designed by Mei Ling. Snake is able to watch the movements of nearby enemies and adjust his movements accordingly, but the radar jams easily.

Spetsnaz: English term for the Russian Special Forces. The word is an acronym for the Russian phrase "spetsialnoe naznachenie," which means "special purpose."

START: Strategic Arms Reduction Talks, a nuclear missile reduction treaty. START 1 and START 2 have already been ratified, and START 3 is scheduled to be signed in the near future.

Stealth camouflage: A new type of camouflage created by ArmsTech, which makes the object blend into the background by performing real-time optic refraction processing in order to render the object as invisible as possible.

Stockholm Syndrome: A psychological response sometimes seen in a hostage, in which the hostage exhibits seeming loyalty to the hostage-taker, in spite of the danger the hostage has been put in.

Super Baby Method: A cloning method in which a human egg is fertilized, and allowed to divide into more than one clone baby. The egg is then transferred to someone's uterus, and a certain number is then intentionally aborted to encourage strong fetal growth for the remaining fetus.

TMD: Theatre Missile Defense, defensive technology designed to deal with the spread of missiles and other weapons of mass destruction. TMDs are designed to intercept short-range tactical missiles.

TNF: Tumour Necrosis Factor. An important cytokine involved in systemic inflammation and the acute phase response.

Totalitarianism: A political doctrine advocating the principle of absolute rule.

UN: United Nations.

VR: Virtual Reality.

Vulcan cannon: A hydraulically or pneumatically driven, six-barreled, air-cooled, electrically fired Gatling Gun with an extremely high rate of fire.

Watergate: A series of scandals occurring during the Nixon administration in which members of the executive branch organized illegal political espionage against their perceived opponents and were charged with violation of the public trust, bribery, contempt of Congress, and attempted obstruction of justice.

White House: The official residence of the President of the United States and his family.

World Eskimo-Indian Olympics: A series of contests based on survival in a harsh climate, held in Alaska once a year.

Yupik: A member of a group of Eskimoan peoples inhabiting the southwest coastal areas of Alaska and extreme north-eastern Siberia, particularly the central part of this range.

Zambezi River: A river of central and southern Africa rising in northwest Zambia and flowing south and west to the Mozambique Channel.

Zanzibar Land: A fortified nation in central Asia ruled by a minority ethnic group.