IFV: Infantry Fighting Vehicle.

IH: International Harvester.

IMP: Individual Meal Pack. Canada’s standard field ration containing precooked entree packed in heavy-duty plastic-foil retort pouch. The equivalent of a U.S. Military Meal Ready to Eat (MRE).

INFOSEC: Information Security.

Intel: Slang shorthand for intelligence.

IR: Depending on context, Infrared or Intelligence Requirement.

Isolator: A device or assembly of devices that isolates or disconnects a telephone or CTS from all wires that exit the SCIF and that has been accepted as effective for security purposes. See also KSU.

IV: Intravenous.

JAG: Judge Advocate General corps. (Military attorneys.)

JBAB: Joint Base Anacostia-Bolling (JBAB), the headquarters of the DIA, in Washington, D.C.

JBLM: Joint Base Lewis-McChord. (Formerly, Fort Lewis and McChord Air Force Base, Washington.)

JP4: Jet Propellant 4, an aviation fuel.

JP5: Jet Propellant 5, an aviation fuel.

JWICS: Joint Worldwide Intelligence Communications System.

Kel-Tec: A Florida gun manufacturer specializing in polymer frame guns.

Kevlar: The material used in most body army and ballistic helmets. “Kevlar” is also the nickname for the standard U.S. Army helmet.

KIA: Killed in Action.

KJV: King James Version of the Bible.

KSU: Key Service Unit. An electromechanical switching device that controls routing and operation of an analog telephone system. See also Isolator and Red/Black.

KTM: An Austrian manufacturer of motorcycles. The K and T are for the surnames of the business founders, Kronreif and Trunkenpolz. The M is for Mattighofen, Austria, the name of the town where the motorcycles are built.

L1A1: The British army version of the FN/FAL, made to inch measurements.

LAR-8: A variant of the AR-10 rifle that accepts FN/FAL or L1A1 magazines.

LAW: Light Antitank Weapon.

LC-1: Load Carrying, Type 1. (U.S. Army Load Bearing Equipment, circa 1970s to 1990s.)

LDS: The Latter-day Saints, commonly called the Mormons. (Flawed doctrine, great preparedness.)

LDSH: Lord Strathcona’s Horse. A regular armored regiment of the Canadian army, headquartered in Edmonton, Alberta, Canada. Members of the regiment are commonly called Strathconas or Strats, for short.

LGP:Le Gouvernement du Peuple (The People’s Government).

Line Conditioning: Elimination of unintentional signals or noise induced or conducted on a telecommunications or information system signal, power, control, indicator, or other external interface line.

LLDR: Lightweight Laser Designator Rangefinder.

LNO: Liaison Officer.

Low Side: An unclassified network. High-side (classified) networks are always physically disconnected (“air gapped”) from low-side networks. This prevents unintentional or intentional copying and pasting of classified information into low-side messages. See also High Side.

LP: Liquid Propane.

LPCs: Leather Personnel Carriers.

LP/OP: Listening Post/Observation Post.

LRRP: Long Range Reconnaissance Patrol.

LZ: Landing Zone.

M1 Abrams: The United States’ current main battle tank, with a 120mm cannon (“main gun”).

M1 Carbine: The U.S. Army semiauto carbine issued during World War II. Mainly issued to officers and second-echelon troops such as artillerymen, for self-defense. It fires .30 U.S. carbine, an intermediate (pistol-class) .30 caliber cartridge. More than six million were manufactured. The folding-stock version designed for use by paratroopers was designated M1A1. See also M2 Carbine.

M1 Garand: The U.S. Army’s primary battle rifle of World War II and the Korean conflict. It is semiautomatic, chambered in .30-06, and uses a top-loading, eight-round en bloc clip that ejects after the last round is fired. This rifle is commonly called the Garand (after the surname of its inventor, John Garand). Not to be confused with the U.S. M1 Carbine, another semiauto of the same era, which shoots a far less powerful pistol-class cartridge.

M1A: The civilian (semiauto only) version of the U.S. Army M14 7.62mm NATO rifle.

M1911: The Model 1911 Colt semiauto pistol (and clones thereof), usually chambered in .45 ACP.

M2 Carbine: The selective-fire (fully automatic) version of the U.S. Army semiauto carbine issued during World War II and the Korean conflict.

M4: The U.S. Army–issue 5.56mm NATO selective-fire carbine. (A shorter version of the M16, with a 14.5-inch barrel and collapsing stock.) Earlier issue M16 carbine variants had designations such as XM177E2 and CAR-15. Civilian semiauto-only variants often have these same designations, or are called “M4geries.”

M4gery: A civilian semiauto-only version of an M4 Carbine, with a sixteen-inch barrel instead of a 14.5-inch barrel.

M9: The U.S. Army–issue version of the Beretta M92 semiauto 9mm pistol.

M14: The U.S. Army–issue 7.62mm NATO selective-fire battle rifle. These rifles are still issued in small numbers, primarily to designated marksmen. The civilian semiauto-only equivalent of the M14 is called the M1A.

M16: The U.S. Army–issue 5.56mm NATO selective-fire battle rifle. The current standard variant is the M16A2, which has improved sight and three-shot burst control. See also M4.

M60: The obsolete U.S. Army–issue 7.62mm NATO belt-fed light machine gun that utilized some design elements of the German MG-42.

M240: The U.S. military variant of the 7.62mm NATO FN-MAG light machine gun. See also FN-MAG.

M249: The U.S. military variant of the 5.56mm NATO FN Minimi light machine gun.

MAG:See FN-MAG.

MAG-58:See FN-MAG.

Maglite: A popular American brand of sturdy flashlights with a machined aluminum casing.

MAPEX: Map Exercise.

MC: Master of Ceremonies.

MCRU: Mobile Control and Reporting Unit.

MG3: A German belt-fed light machine gun, chambered in 7.62mm NATO.

MG4: A German belt-fed light machine gun, chambered in 5.56mm NATO.

MI: Military Intelligence. See also CI, HUMINT, and SIGINT.

Mini-14: A 5.56mm NATO semiauto carbine made by Ruger.

Minimi:See M249.

MOIS: Ministry of Intelligence and Security, the Iranian spy agency. See also VEVAK.

MOLLE: Modular Lightweight Load-carrying Equipment.

Molotov cocktail: A hand-thrown firebomb made from a glass container filled with gasoline or thickened gasoline (napalm).

MOS: Military Occupational Specialty.

MP: Military Police.

MRAP: Mine Resistant Ambush Protected (vehicle).

MRE: Meal Ready to Eat. See also IMP and CR1M.

MRI: Magnetic Resonance Imaging.

MSS: Depending on context, Ministry of State Security or Modular Sleep System.

MTBE: Methyl tert-butyl ether. An oxygenating additive for gasoline.

MultiCam:See OCP.

MURS: Multi Use Radio Service. A VHF two-way radio service that does not require a license. See also FRS and GMRS.

MVPA: Military Vehicle Preservation Association.

MWR: Morale, Welfare, and Recreation.

NAB: Naval Amphibious Base.

Napalm: Thickened gasoline, used in some flame weapons.

NATO: North Atlantic Treaty Organization.

NBC: Nuclear, Biological, and Chemical.

NCO: Noncommissioned Officer.