This site contains a comprehensive list of U.S. military terms and definitions.
G Gain G1 Assistant Chief of Staff, G1 (Personnel) G2 or G-2 (1) Assistant Chief of Staff, G2 (Intelligence); (2) Army or Ground Directorate of Intelligence; (3) General Corps Staff Intelligence Officer G3 Assistant Chief of Staff, G3 (Operations and Plans) G4 Assistant Chief of Staff, G4 (Logistics) G5 Assistant Chief of Staff, G5 (Civil Affairs) G6 Director(ate) of C4 G8 Director(ate) of Resource Management GA Ground Attack GaAs Gallium Arsenide GACC Ground Attack Coordination Center GAD Guards Artillery Division GADT Ground/Air Defense Threat GAF Ground Alert Facility (of PAC ABNCP) GAFIA German Armed Forces Intelligence Agency GALE Generic Area Limitation Environment GALS FSU Satellite (“Horizon”) GAMO Ground and Amphibious Military Operations GAO General Accounting Office GAS (1) Gray Area Systems; (2) Getaway Special GAT (1) Government Acceptance Test; (2) Guidance, Apportionment, and Targeting GATT General Agreement on Tariffs and Trade (UN) GB (1) Gigabyte; (2) Guardband GBCS(-L or -H) Ground-Based Common Sensor (-Light or -Heavy) GBI Ground-Based Interceptor GBL Ground-Based Laser GBMD Global Ballistic Missile Defense GBR Ground-Based Radar GBS Global Broadcast System GBU Guided Bomb Unit GC Gun Camera GCA Ground Controlled Approach GCC (1) Government Control Center; (2) Ground Component Commander; (3) Gulf Cooperation Council; (4) Global Control Center GCCS (1) Ground Command and Control System; (2) Global Command and Control System GCDCAL Great Circle Distance Calculator GCE Ground Combat Element GCI Ground-Controlled Intercept GCN Ground Communications Network GCNTTY Ground Communications Network Teletype GCP Ground-Controlled Processor GCP-E Ground-Controlled Processor-ELINT GCS (1) Graphics Compatibility System; (2) Ground Control Station; (3) Global Connectivity Services; (4) Global Communications System GCSS Global Combat Support System GDA Gimbaled Dish Antenna GDBI Generic Data Base Interface GDBMS Generic Data Base Management Server GDIC General Defense Intelligence Community GDIP General Defense Intelligence Program GDIPP General Defense Intelligence Proposed Program GDL Gas Dynamic Laser GDOP Geometric Dilution of Precision GDP (1) General Defense Plan; (2) Gross Defense Product; (3) Ground Defense Position; (4) Gross Domestic Product GDPS Ground Data Processing System GDRS Ground Data Reduction System GDS (1) General Declassification Schedule; (2) FSU Guards; (3) Group Decision Support GDSS Global Decision Support System GDT Ground Data Terminal Gen General GEM Ground Effects Machine GEN (1) Generation; (2) General GENIC German National Intelligence Cell (NATO) GENREP General Reports GENSER General Service (Communications) GEO Geosynchronous Earth Orbit GEODIS Geographic Display GEODSS Ground-Based Electro-Optical Deep-Space Surveillance System GEOFILE (1) Geographic Locations Code File System; (2) Geolocation File (JOPES) GEOREF Global Reference System, a worldwide position reference system that may be applied to any map or chart graduated in latitude and longitude regardless of projection. GEOSAT Geological Satellite GEP Ground Entry Point GEPS Generic Electronic Publishing System GES Ground Entry Station GFAC Ground Forward Air Controller GFCP Generic Front-End Communications Package GFE Government Furnished Equipment GFTD Global Force Trends Data Base GFR Gap Filler Radar GGI&S Global Geospatial and Information Services GHz Gigahertz GIGSTER NSA Video Teleconferencing System GIIPS Geographic Installation Intelligence Production Specifications GIITS General Intelligence Imagery Training System GIN Greenland-Iceland-Norway GIPD (1) General Intelligence Production Detachment; (2) General Intelligence Production Division GIPMIS General Intelligence Production Management Information System GIPS Geographic Installation Intelligence Production Specifications GIPSY Graphics Information or Presentation System GIS Geographical Information System GIST Graphical Intelligence Support Terminal GITAC General Intelligence Training Advisory Committee GITC General Intelligence Training Center GITS General Intelligence Training System GIUK Greenland-Iceland-United Kingdom GKNT State Committee for Science and Technology (FSU) GKS Graphics Kernel System GL Grenade Launcher GLCM Ground-Launched Cruise Missile GLLD U.S. Ground Laser Locator Designator (for COPPERHEAD) GLMX Geological Multi-Source Exploitation (System) GLOBIXS Global Information Exchange System GLOMR Global Low-Orbiting Message Relay GLONASS Global Navigation Satellite System GM Guided Missile GMD Global Missile Defense GMF Ground Mobile Forces GMFP Global Military Force Policy GMFSC Ground Mobile Force Satellite Communications GMI (1) General Medical Intelligence; (2) General Military Intelligence GMIPP General Military Intelligence Production Plan GMIT Ground Military Intelligence Team (ROK) GMRD Guards Motorized Rifle Division (FSU) GMS (1) Ground Mobile System; (2) Geostationary Meteorological Satellite; (3) Ground Mission Supervisor GMT Greenwich Mean Time (Zulu) GMTI Ground Moving Target Indicator GNAS Gateway Network Access System GNC Global Navigation Chart GND Ground GNP Gross National Product GNS Global Network Segment GNST Glossary of Naval Ship Types GO() Government of (Name of Country) G-O Office of Law Enforcement and Defense Operations (USCG) G-OINS Intelligence Division (USCG/G-O) G-OIS Investigations and Security Division (USCG/G-O) GOB Ground Order of Battle GOC (1) General Officer Commanding (UK); (2) Government of Canada; (3) Global Operations Center GOCO Government Owned Contractor Operated GOES Geostationary Operational Environmental Satellites GOLDS General On-Line Display System GOLDWING Army HF Radio; HF communications system for meteorological and other operations GOMS Geostationary Operational Meteorological Satellite GOP Generated Option Plan GOR General Operational Requirement GORB General Officer Review Board GOS Grade of Service GOSC General Officer Steering Committee GOSIA Government Open System Interconnect Architecture GOSIP Government Open Systems Interconnected Profile GOSPLAN State Planning Committee (FSU) GOSSNAB State Committee for Material-Technical Supply (FSU) GOTS Government Off-the-Shelf GP (1) Group; (2) General Purpose GPALS Global Protection Against Limited Strikes GPEE General Purpose Encryption Equipment GPF (1) General Purpose Forces; (2) Ground Processing Facility gph Gallons Per Hour GP NAF General Purpose Numbered Air Force GPNDS Global Positioning & Nuclear Detection System GPO Government Printing Office GPS (1) Global Positioning System; (2) Grid Producing Source; (3) Geographical Positioning System; (4) Ground Processing Stations GPSCS General Purpose Satellite Communications System GR (1) Graphical Reporting; (2) Gateway Router GRAD Graduate GRANITE SENTRY Proper Name of System GRID Brand of Portable PC GRIPF GUARDRAIL Integrated Processing Facility GRD Ground Resolved Distance GREEN FLAG ACC live-fly electronic combat exercise GRG Gridded Reference Graphic GRO Gamma Ray Observatory GROFIS Ground Forces Intelligence Study GRP Glass Reinforced Plastic GRT Gross Registered Tonnage GRU FSU General Staff Intelligence Organization GS (1) General Staff, (2) General Support; (3) Geological Survey; (4) General Schedule; (5) General Service; (6) Government Service (Federal Civil Service); (7) Ground Station; (8) Government Civilian GSA General Services Administration GSD (1) Ground Sample Distance; (2) Graphical Situation Display GSE Ground Support Equipment GSF (1) Ground Support Fighter (FSU); (2) Group of Soviet Forces; (3) Ground Station Facility GSFC Goddard Space Flight Center GSFG Group of Soviet Forces Germany GSFM Group of Soviet Forces Mongolia GSICS General Support Interim Contractor Support GSM (1) Ground Support Module (JSTARS); (2) Ground Station Module GSOAF GGI&S Special Operations Applications Facility GSP General Strike Plan GSR (1) General Support Reinforcing; (2) Ground Surveillance Radar GSRS U.S. General Support Rocket System GSS (1) Global Support System; (2) General System Specification GST (1) Ground Sensor Terminal; (2) Ground Station Terminal; (3) Ground Support Terminal GSTS Ground-Based Surveillance and Tracking System GSTN General Switched Telephone Network GSU Geographically Separated Unit G/T Ratio of Antenna Gain to Noise Temperature GTA Government Training Aid GTAB Global Transportation Analysis Bulletin GTD Guards Tank Division (FSU) GTN Global Transportation Network GTS Global Telecommunications Service GTC Gas Turbine Compressor GTTC Goodfellow Technical Training Center GUI Graphics User Interface GW (1) Guided Weapon; (2) Gateway; (3) Guerrilla Warfare G/W Gateway GWC Global Weather Control GWEN Ground Wave Emergency Network GWIC Great Wall Industries Corporation (China) GWIP Global Weather Intercept Program GWP General Work Plan GW/R Gateway/Router GWS Gaps, Weaknesses, and Shortfalls (also GW&S) GYRO Gyroscope or Gyroscopic GZ Ground Zero