Defense Glossary

EAR Export Administration Regulations

The US Commerce Department export-control regime for dual-use and less-sensitive military items, the counterpart to ITAR for goods that aren't purely military.

FMS Foreign Military Sales

The US government-to-government process for selling defense equipment and services to allied nations, run by the Defense Security Cooperation Agency.

ITAR International Traffic in Arms Regulations

The US export-control regime that governs defense articles, technical data and services on the US Munitions List, administered by the State Department.

APFSDS Armor-Piercing Fin-Stabilized Discarding Sabot

A tank gun round that discards a lightweight outer sleeve after leaving the barrel, leaving a long, dense metal dart to punch through armor using speed and mass alone, with no explosive warhead involved.

ATGM Anti-Tank Guided Missile

A guided missile fired by infantry, vehicles or aircraft to destroy armored targets at range, correcting its own flight path onto the target rather than flying a fixed unguided trajectory like a rocket.

Combat Radius

The maximum out-and-back distance an aircraft can fly on a mission with a combat load and still return with a safe fuel reserve, distinct from its one-way ferry range.

ECM / ECCM Electronic Countermeasures / Counter-Countermeasures

ECM is deliberate electronic trickery, jamming, decoys, spoofing, used to defeat radar and other sensors; ECCM is the set of design features and techniques built to keep working despite that trickery.

EW Electronic Warfare

Military action that uses the electromagnetic spectrum to sense, deceive, or disable an adversary's radar, radios, and guided weapons, often without firing a shot at all.

IFF Identification Friend or Foe

A transponder-based system that lets radar and air-defense operators ask an aircraft or vehicle whether it is friendly before deciding to engage it.

IFV Infantry Fighting Vehicle

An armored vehicle that carries an infantry squad into battle while also fighting alongside them with its own cannon and often an anti-tank missile, unlike a lightly armed troop-carrying APC.

MANPADS Man-Portable Air-Defense System

A shoulder-fired, infrared-guided surface-to-air missile that a single soldier can carry, aim, and fire without a vehicle or radar system.

MBT Main Battle Tank

A tracked, heavily armored ground combat vehicle built around a large-caliber main gun, designed to fight other armored vehicles and fortified positions on the direct-fire battlefield.

RHA Rolled Homogeneous Armor

The uniform hot-rolled steel armor standard used as the common baseline for measuring both armor protection and projectile penetration in millimeters.

ISR Intelligence, Surveillance and Reconnaissance

ISR is the combined discipline of collecting, processing, and delivering information about an adversary, using satellites, drones, aircraft, and sensors, so commanders can decide and act instead of guessing.

SEAD / DEAD Suppression / Destruction of Enemy Air Defenses

SEAD is the mission of neutralizing an enemy's radars and surface-to-air missiles long enough for a strike package to get through; DEAD is the harder version, permanently destroying that same air-defense network.