| AAW | antiaircraft warfare |
| ABI | airborne-based interceptor |
| ABIR | airborne infrared |
| ABL | Airborne Laser |
| ABM | antiballistic missile |
| ABMDA | Advanced Ballistic Missile Defense Agency |
| ABT | air-breathing threat |
| ADSAM | air-directed surface-to-air missile |
| AEU | antenna equipment unit |
| AHTK | airborne hit-to-kill |
| ALHK | air-launched hit-to-kill |
| ALTB | airborne laser test bed |
| AMRAAM | advanced medium-range air-to-air missile |
| AN/TPY | Army Navy/transportable radar surveillance |
| AO | adaptive optics |
| APS | American Physical Society |
| ASAT | antisatellite |
| ASUW | antisurface warfare |
| ASW | antisubmarine warfare |
| ATR | automatic target recognition |
| AUPC | average unit production cost |
| BAMBI | ballistic missile boost intercept |
| BILL | beacon illuminator laser |
| BMC2 | battle management command and control |
| BMC3 | battle management command, control, and communications |
| BMC4I | battle management command, control, communications, computing, and intelligence |
| BMD | ballistic missile defense |
| BMDO | Ballistic Missile Defense Office |
| BPI | boost-phase intercept |
| C2 | command and control |
| C2BMC | command and control battle management center |
| C3 | command, control, and communications |
| C3I | command, control, communications, and intelligence |
| CAP | combat air patrol |
| CBO | Congressional Budget Office |
| CE | capability enhancement |
| CEU | cooling equipment unit |
| COCOM | combatant commander |
| COIL | chemical oxygen-iodine laser |
| CONOPS | concept of operations |
| CONUS | continental United States |
| CSV | cable support vehicle |
| DACS | divert and attitude control system |
| DARPA | Defense Advanced Research Projects Agency |
| DEM/VAL | demonstration and validation |
| DISA | Defense Information System Agency |
| DOD | Department of Defense |
| DOE | Director of Estimating |
| DOF | degrees of freedom |
| DOT | Department of Transportation |
| DSP | Defense Support Program |
| DTRM | dual-thrust rocket motor |
| ECS | engagement control station |
| EEU | electronic equipment unit |
| EKV | exoatmospheric kill vehicle |
| EMD | engineering and manufacturing development |
| EO | electro-optics |
| EOR | engage on remote |
| EPP | electronic power plant |
| ERIS | exoatmospheric reentry interceptor system |
| EWS | early warning system |
| FAIR | fly along infrared |
| FBX | X-band radar (stand-alone version) |
| FEWS | future early warning system |
| FGA | Fort Greely, Alaska |
| FLIR | forward-looking infrared |
| FOC | final operational capability |
| FY | fiscal year |
| FYDP | future years defense plan |
| GBI | ground-based interceptor |
| GBR | ground-based radar |
| GBX | ground-based X-band radar |
| GEO | geosynchronous orbit |
| GMD | Ground-Based Midcourse Defense |
| GMD-E | Ground-Based Midcourse Defense-Evolved |
| HALO-2 | High Altitude Observatory 2 (program) |
| HEL | high-energy laser |
| HF/DF | hydrogen fluoride/deuterium fluoride |
| HTK | hit to kill |
| IBCS | integrated battle command system |
| ICBM | intercontinental ballistic missile |
| IDT | IFICS data terminal |
| IFICS | in-flight interceptor communications station |
| IFTU | in-flight target update |
| IOC | initial operational capability |
| IOT&E | initial operational test and evaluation |
| IR | infrared |
| IRBM | intermediate-range ballistic missile |
| ITOF | interceptor total time of flight |
| KEI | kinetic energy interceptor |
| KKV | kinetic-kill vehicle |
| KV | kill vehicle |
| LADAR | laser detection and ranging (laser radar) |
| LCC | life-cycle cost |
| LOR | launch on remote |
| LOS | line of sight |
| LRIP | low rate initial production |
| LSRBM | long- and short-range ballistic missiles |
| LWIR | long-wave infrared |
| MCS | mission control system |
| MDA | Missile Defense Agency |
| MDIOC | Missile Defense Integrated Operations Center |
| MEADS | Medium Extended Air Defense System |
| MILCON | military construction |
| MKV | multiple kill vehicle |
| MRBM | medium-range ballistic missile |
| MSE | missile segment enhancement (improved PAC-3) |
| MSX | midcourse space experiment |
| MTS-B | multispectral targeting system, version B |
| NAS | National Academy of Sciences |
| NASA | National Aeronautics and Space Administration |
| NATO | North Atlantic Treaty Organization |
| NCADE | network-centric airborne defense element |
| NGAM | next-generation Aegis missile |
| NMD | national missile defense |
| NRC | National Research Council |
| O&S | operations and support |
| O&S sunk | operations and support (expended) |
| OC | operations central |
| OSD | Office of Secretary of Defense |
| PAA | Phased Adaptive Approach |
| PAC-3 | Patriot Advanced Capability 3 |
| PB | President’s budget |
| PBDI | postboost, predeployment intercept |
| PG | precision-guided |
| PTSS | Precision Tracking and Surveillance System |
| R&D | research and development |
| RCS | radar cross-section |
| RDT&E | research, development, testing, and evaluation |
| RF | radio frequency |
| ROE | rules of engagement |
| ROM | rough order of magnitude |
| RS | radar set |
| RV | reentry vehicle |
| S&T | science and technology |
| SAM | surface-to-air missile |
| SBI | space-based interceptor |
| SBX | sea-based X-band radar |
| SBIRS | spaced-based infrared aystem |
| SDACS | solid divert and atitude control system |
| SECDEF | Secretary of Defense |
| SES | shoot-engage-shoot |
| SFS | shoot-fail-shoot |
| SLS | shoot-look-shoot |
| SM | standard missile |
| SM-3 | Standard Missile-3 |
| SMRBM | short- and medium-range ballistic missiles |
| SPY-1 | naval phased-array radar |
| SRBM | short-range ballistic missile |
| STSS | Space Tracking and Surveillance System |
| T2Go | time to go |
| TBM | theater ballistic missile |
| TBMD | theater ballistic missile defense |
| TDACS | Throttleable Divert and Attitude Control System |
| TEL | transporter erector launcher |
| TFCC | THAAD fire control and communications |
| THAAD | Terminal (formerly theater) High-Altitude Area Defense |
| TILL | tracking illuminator laser |
| TOM | target object map |
| TOS | tactical operations station |
| TPY-2 | forward-based X-band radar |
| T/R | transmit/receive |
| TRL | technology readiness level |
| TSC | theater surface combatant |
| TSG | tactical support group |
| TSRM | third-stage rocket motor |
| TWAA | tactical warning and attack assessment |
| UAV | unmanned aerial vehicle |
| UEWR | upgraded early warning radar |
| UHF | ultrahigh frequency |
| USA | United States Army |
| USAF | United States Air Force |
| USMC | United States Marine Corps |
| USN | United States Navy |