This glossary covers common terms, abbreviations and acronyms you will find on Airsoftsociety.com as well as other airsoft forums. This glossary covers multiple categories of terms including airsoft guns, accessories, teching, gear and optics.

Term - Definition
ACOG - - Advanced Combat Optical Gunsight a telescopic sight made by Trijicon but airsoft replicas are often simple Red dot sights.

Light Camera accessory Auto part Cylinder Optical instrument

ACOG replica

ACU - Army Combat Uniform. Current battle dress in the US Army. Replaced the BDU.

AEG - Automatic Electric Gun. An airsoft gun that is powered by an electric motor and gearbox.

AEP - Automatic Electric Pistol. A pistol that has a small gearbox and motor and operates similarly to an AEG.

AFG - Angled Foregrip. A type of vertical grip made by Magpul.
Air gun Trigger Machine gun Shotgun Gun barrel
AFG on M4 RAS

AK - Short for Kalashnikov-type replicas.

ANSI - American National Standards Institute. A nonprofit organization that sets standards for products and services. In airsoft, usually, refers to eye protection that is rated to ANSI standard Z87 for impact resistance.

AOE - Angle of Engagement. The angle in which the sector gear meets the teeth on the piston.

AOR - Area of Responsibility. Camouflage patterns (AOR1 and AOR2) used in the NWU.

AR - Short for AR-15 or M16-type replicas (including M4s).

ARL - Anti-Reversal Latch. Part of gear box that prevents the gears in a reverse direction after the spring is compressed.

Balance charger - A battery charger used to charge Li-Po and Li-Fe batteries. Has an extra plug for balancing.

BASR - Bolt-action sniper rifle. An airsoft replica of a sniper rifle powered by pulling back a spring.
Gas Gun accessory Metal Auto part Event
Close-up of pull-back bolt on a BASR

BBU - Blowback Unit. The internal part in a GBB that causes the recoil.

BDU - Battle Dress Uniform. Camouflaged fatigues used in combat situations. Replaced by the ACU.

Bios - Biodegradable BBs. BBs that will dissolve over time and are more environmentally friendly.

Black Gas - Very powerful gas used in cold weather. Use in normal temperatures can damage most guns.

Bore Up - A type of cylinder that has a larger inner diameter giving more air and subsequently more FPS in an AEG

Bucking - A part of the hop up unit that is composed of a tube that goes over the barrel

Buffer Tube - Part of an AR-style rifle that the stock attaches to
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Buffer tube on an M4-style AEG


Bullpup - A weapon with the magazine located behind the trigger/grip
Air gun Trigger Gun barrel Gun accessory Composite material
Magazine in bullpup configuration.

CCW - Counter Clockwise (sometimes called anti-clockwise). Usually, refers to threading on the end of the barrel. Used to match correct barrel accessories, e.g., suppressors.

CH - Cylinder Head. The end of the cylinder closest to the barrel.

Chrono - Chronometer. A device that measures FPS and ROF. When used as a verb, e.g., "to chrono" indicates use of a chronometer.
Camera accessory Gadget Measuring instrument Audio equipment Camera lens
Chronometer

CM - Combat Machine. A popular AEG manufactured by G&G.

CNC - Computer Numeric Control. A type of machining process that can make precise complex forms.

COL - Cut off Lever. A lever that interacts with the sector gear to change between semi- and full-auto fire.

CO2 - Carbon dioxide. A gas that is more powerful than green gas used to power airsoft guns. Comes in pre-filled cartridges.

Cooldown - Cooldown effect is seen in GBBs. Rapid firing will cause the gas to lower its temperature, reducing efficiency and performance.

CQB - Close Quarter Battle. A game type with close range encounters or can refer to a weapon with a shorter barrel and lower FPS.

CRB - Carbine. A version of a rifle with a shorter barrel.

CW - Clockwise. Usually refers to threading on the end of the barrel. Used to match correct barrel accessories, e.g., suppressors.

Daytona - A gun with a kit installed that allows it to run off HPA as well as provide recoil.

Deans - Type of battery connector felt superior to the Tamiya connector and can handle higher voltages.
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Deans connectors

Delta Ring - A ring between the rear of the front handguards and the upper receiver in AR-style rifles that holds the handguards in place.

DMR - Designated Marksman Rifle. A rifle designed for increased accuracy at longer ranges. Often limited to semi-auto fire only.

DSG - Dual Sector Gear. A sector gear that gives two shots per rotation, giving a high rate of fire. Builds with a DSG can be difficult.

Duster Gas - Also known as HFC-134a, this is the gas used in aerosol electronic duster cans. It is the weakest gas and recommended by some Asian GBB pistol makers.

EBB - Electric Blow Back. A feature in some AEGs to simulate recoil.

EBR - Enhanced Battle Rifle. A modernized version of the M14 rifle.

ELCAN - A line of optical sights made by Raytheon.

EoTech - A company that made combat holographic sights. Airsoft replicas are often simple Red dot sights.
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Replica EoTech holographic sight

Eye Relief - The distance between the eyepiece lens and the pupil of the eye to allow optimum viewing of an optic, e.g., scope.

FCU - Fire control unit. Allows you to change the ROF and add a burst mode in an AEG.

FDE - Flat Dark Earth. A coloration used in the military.

FET - See MOSFET.

FG - Foliage Green. A coloration used in the military.

Flash Mag - A hi-cap mag that is wound using a pull string on the bottom of the magazine, mechanically it works just like a hi-cap.

Flat Hop - Simpler than the R-hop, can yield a moderate increase in range.

FPS - Feet per second. Usually refers to the velocity of the BB as it leaves the gun.

Free Float - Type of rail system that is attached directly to the receiver and does not touch the barrel.

Full Seal - Refers to a type of goggles or mask that does not allow any space between the device and the face. Often required by many fields.

G-series - Refers to Glock-style replicas.

GB - Gearbox. See definition below.

GBB - Gas Blowback (Pistol). A pistol that is powered by gas and had a movable slide.

GBBR - Gas Blowback Rifle. A rifle using gas rather an electricity to power the BBs. More realistic than AEGs in terms of recoil and breakdown. Compare with AEG.
Gearbox - The internal set of parts that create the working mechanism of an AEG.
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Cutaway of AEG gearbox

Green Gas - Standard gas for GBB pistols which is unscented propane.

Hi-cap - High capacity magazine. Magazine holding 300+ rounds. Often requires intermittent winding.

Hop Up - Device between the barrel and gearbox that creates backspin on a BB. This is to extend effective range.
Camera Camera lens Lens Camera accessory Cameras & optics
Rotary-style hop up unit

HPA - High Powered Air. Method of powering a gun using compressed air from an external tank and a regulator.

HS - High Speed. Can refer to a motor or a gear set.

HT - High Torque. Can refer to a motor or a gear set.

Iron Sights - Simple sighting markers on a gun. Can be fixed or adjustable.

Joule Creep - A phenomenon where using heavier BBs will give a higher energy than lighter ones using the same gun. Caused by more efficient transfer of energy in heavier ammo.

Keymod - An interface system proposed as a successor to the standard picatinny rail system.
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Keymod RIS

Killflash - A mesh cover to protect an optic from being hit by a BB.
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Killflash

Li-Fe - Lithium Iron Phosphate (battery). A battery similar to Li-Po's but theoretically safer. Not as popular as Li-Po's.

Li-Po - Lithium-polymer (battery). A battery that is usually smaller and more efficient than standard Nickel-cadmium or Nickel-Metal hydride batteries.

LMG - Light Machine Gun - replica that replicates a support weapon. Often has a box magazine and lmited to full-auto fire.

Low-cap - Low Capacity Magazine. Magazine holding less than 100 rounds.

Lower - Lower receiver. The bottom portion of a rifle body.

LPAEG - Low-powered automatic electric gun. A gun with low FPS often powered by AA batteries. Uses lighter BBs, e.g., .12gm.

LPEG - Low-powered electric gun - see LPAEG.

M100 - Measurement of spring strength. The higher the number the higher the FPS.

MAEG - Mini AEG. A less than 1:1 scale model of a gun powered by a lower power motor. See also AEP.

Mag - Magazine. A component of a gun (usually detachable) that contains the ammunition.

Magwell - The part of the gun in which a detachable magazine is inserted.
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Magwell of an AR lower receiver

MARPAT - Marine Pattern. A type of camouflage pattern.

MED - Minimum engagement distance, the distance at which you must be (at minimum) to shoot at an enemy.

MICH - Modular Integrated Communications Helmet. A helmet style used by the US Army.

Mid-cap - Middle capacity magazine. Magazine holding between 100 and 300 rounds.

MilSim - Military Simulation. A game type involving realistic weapons and loadouts (including limited ammunition). Scenarios can be historical.

M-Lok - An alternative interface (rail) system developed by Magpul.

MOE - Magpul Original Equipment - Usually used to refer to magpul furniture for M4s.

MOLLE - Modular Lightweight Load Carrying Equipment. Current standard for belts and vests. Various accessories may be attached via webbing.

MOSFET - Metal Oxide Semiconductor Field-Effect Transistor - Used in AEGs to preserve trigger contacts.

MPEG - Mid-priced Electric Gun - guns priced above LPEGs with somewhat better quality.

Multicam - A multiple color camouflage pattern developed by Crye Precision and used by the US Army.

NBB - Non-blowback. Usually, refers to a pistol that has no or limited travel of the slide after firing.

Neo - Neodymium motor - neodymium magnets in the motor give more speed and torque than a standard ferrite motor.

NiCd - Nickel Cadmium. Oldest and most problematic of the rechargeable battery types.

NiMh - Nickel Metal Hydride. Type of rechargable battery.
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NiMh battery with mini-Tamiya connector

NOD - Night optical device. An optic that allows sighting in low-light conditions.

NPAS - Negative Pressure Air System. Used to regulate FPS in a GBBR.

Nub - Part of the hop up unit that presses on the bucking to increase friction and backspin. Also called a spacer.

NVG - Night Vision Goggles. Goggles that allow visualization in low-light conditions. Often attached to a helmet.

NWU - Navy Working Uniform - similar to the ACU but for the US Navy.
OD - Olive Drab. A coloration used in the military.

OEM - Original Equipment Manufacturer - on a re-branded product, who actually made the product.

Optic - A device used to assist aiming, e.g., red dot or scope. Rated by magnification and lens diameter, e.g., 4x-32 is 4x magnification and 32mm lens.

Overhop - A condition where too much backspin causes the BB to fly upwards.

Overspin - When a gearbox cycles more than 1 time per pull of the trigger. Usually from a weaker spring, a stronger motor or using a high-voltage battery.

P* - Polarstar.

Paracord - Parachute cord. A lightweight braided nylon rope not only used in parachutes but for general use.

PDW - Personal Defense Weapon - usually a shorter version of an existing weapon..

PEQ - A box attached to the front of a weapon with a flashlight and/or laser. Dummy boxes can be used to store a battery for an AEG.

PH - Piston Head. The top of the piston, i.e., the end that pushes the air out.
Camera accessory Camera Cameras & optics Gadget Engineering
Dummy PEQ box

Picatinny - The current standard for accessory rails (also called MIL-STD-1913).

Plate Carrier - A type of tactical vest that allows the addition of body armor.

PMAG - A polymer magazine made by Magpul for AR-style guns. Magpul makes replicas for airsoft.

PME - Premature engagement. When the sector gear engages the piston rack prematurely.

Polarstar - An AEG that has been converted to use HPA and has an FCU installed. ROF and FPS can be adjusted.
Air gun Trigger Peripheral Gun barrel Input device
Polarstar M4 with tank and hose

PTW - Profesional Training Weapon. Originally a line of AEGs from Systema with realistic features, the term is sometimes used with other AEGs with similar features.

QC - Quick Change. Able to be changed more quickly, often refers to AEG springs.

QD - Quick Detach. Able to quickly remove, e.g., without unscrewing.

R-Hop - A hop-up mod that is moderately difficult to perfect, but yields an immense increase in range.

Radius - To round the corners of the cylinder window of the gearbox shell to strengthen it.
Wood Wood stain Gun accessory Hardwood Gas
Gearbox shell with radius cylinder window

RAS - Rail Attachment System - See RIS.

Receiver - The "body" of a gun. Consists of an upper receiver and lower receiver.

RDS - Red Dot Sight. A non-magnified optic that has a red-dot to help aim.

Red Gas - Chlorodifluoromethane (R22 or HCFC-22). More powerful than green gas but banned due to environmental reasons.

RIS - Rail Interface System. An accessory that replaces the foregrip portion of an AEG with rails on it.

RMR - Ruggedized Miniature Reflex. A small optical sight made by Trijicon. Can be used on pistols.
Trigger Air gun Bumper Automotive exterior Gun barrel
mounted on pistol slide

ROF - Rate of Fire. Number of BBs fired per unit of time usually measured in Rounds per Second.

RS - Real Steel. Used to describe actual firearms.

Rubber - As in Hop Up Rubber - see Bucking.

SAI - Salient Arms International. A company that customizes RS guns. SAI replicas are often seen in airsoft.

SAW - Squad Automatic Weapon - See LMG.

Sector Gear - The gear that interfaces with the teeth on a piston.

Shim - A spacer placed in the gearbox to better align the gears.

Short Stroking - Removing teeth from piston and sector gear resulting in a higher ROF but loss of FPS.

Sling Point - Attachment points on a firearm to which a sling is attached. E.g., two-point sling.
Air gun Trigger Gun barrel Machine gun Gun accessory
3-point sling

Smart Charger - A battery charger that stops charging when the battery is full. Safer than a wall charger charging NiCd and NiMH batteries.

Sorbo - Sorbothane. An impact absorbing material that reduces wear on the gearbox that comes in pad form.
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Sorbo pad

SpeedSoft - A game type where speed and maneuverability create a fast-paced game.

Split Gearbox - Gearbox design seen in AEGs by ICS. Easier to switch upper receivers and easier to work on.

Sportline - Usually the budget line of a manufacturer. Typically has a plastic body and lower quality internal parts.

SPR - Special Purpose Rifle. A term used by Krytac to describe its longer barreled airsoft gun.

Springer - An airsoft gun powered by manually compressing a spring.

SSG - Single Sector Gear. A sector gear that gives one shot per rotation. Most sectors gears are SSGs.

T-1 - A micro red dot optic made by Aimpoint.

TACO - A type of modular magazine pouch made by HSGI.

Tappet Plate - A flat metal piece that interfaces with the sector gear to chamber a BB.

Tamiya - Most common type of battery connector in airsoft guns. Originated from RC car batteries and comes in two sizes: Large and Mini.

TBB - Tight-Bore Barrel. A barrel with a smaller inner diameter than stock barrels. Diameter is often listed in mm, e.g., TBB 6.01.

Tech - A person with sufficient skill to repair or upgrade airsoft guns. When used as a verb "to tech", it means to work on airsoft guns.

TM compatible - Tokyo Marui compatible. The most common standard for upgrade parts.

Top Gas - Synonym for Green Gas. Top was a specific brand of green gas.

TPA - Turns per Armature. Measure of motor. Higher TPA = more torque, less speed.

Tracer Unit - An accessory when placed at the end of a barrel will make BBs glow in the dark. Needs special BBs.

Tri-shot - Airsoft shotgun with three barrels that fires 3 BBs per trigger pull.

UCP - Universal Camouflage Pattern -US Army camouflage pattern similar to MARPAT.

Upper - Upper receiver. The upper part of a rifle body.

V2 - Version 2 gearbox (used in M4 style AEGs). V3s are AK-style. Common types are V1-V7.

Weaver - A rail system similar to Picatinny but with narrower and shallower slots. Picatinny devices may not fit on a Weaver rail.
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Weaver RIS

WIP - Work in Progress

Thanks to Airsoft444, AnotherM4Normie and everyone else on the Abbreviations thread that Husker started.