| 3PL | Third-party logistics |
| 4PLs | Fourth-party logistics companies |
| AC | Alternating Current |
| ACC | Adaptive Cruise Control |
| ADA | Americans with Disabilities Act |
| ADF | aircraft deicing fluid |
| ADS-A | automatic dependent surveillance-addressable system |
| ADS-B | automatic dependent surveillance-broadcast |
| AIADA | American International Automobile Dealers Association |
| AIADA | American Imported Automobile Dealers Association |
| AIR-21 | Aviation Investment and Reform Act for the 21st Century |
| AM radio | lower frequency radio waves |
| API | American Petroleum Institute |
| ASRS | Aviation Safety Reporting System |
| ASTs | aboveground storage tanks |
| ATC | Air Traffic Control |
| ATO | Air Traffic Organization |
| AVL | Automatic Vehicle Location |
| AVP | Advanced Vehicle Technologies Program |
| B2B | business-to-business |
| B2C | business-to-consumer |
| BAC | Blood Alcohol Concentration |
| BART | Bay Area Rapid Transit |
| BBC | British Broadcasting Corporation |
| Bbl | barrel |
| Big LEO | special handheld telephone |
| BTS | Bureau of Transportation Statistics |
| Btu | British Thermal Unit |
| C02 | Carbon dioxide |
| CAB | Civil Aeronautics Board |
| CAD | Computer-Aided Dispatch |
| CAF | Corporate Average Fuel Economy |
| CD-ROM/DVD | Compact Disk-Read Only Memory/Digital Video Disk |
| CDL | Commercial Drivers License |
| CDS | Crashworthiness Data System |
| CFIT | controlled flight into terrain |
| CH4 | Methane |
| CNG | Compressed Natural Gas |
| CO | Carbon Monoxide |
| COMSTAC | Commercial Space Transportation Advisory Committee |
| CONUS | Continental U.S. |
| COO | Chief Operating Officer |
| CORS | Continuously operating reference stations |
| CPDLC | Controller-Pilot Data Link Communications |
| CRAF | Civil Reserve Air Fleet |
| CVO | Commercial Vehicles Operations |
| DBA | Decibels |
| DC | Direct Current |
| DFDRs | Digital flight data recorders |
| DGPS | Differential GPS |
| DOD | Department of Defense |
| DOJ | Department of Justice |
| DVD | Digital Video Disk |
| ECP | Electronically Controlled Pneumatic |
| EDI | Electronic Data Interchange |
| EDSs | Explosives Detection Systems |
| EMS | Emergency Medical Services |
| EPA | Environmental Protection Agency |
| ERGS | Electronic Route Guidance System |
| ETC | Electronic Toll Collection |
| EU | European Union |
| FAA | Federal Aviation Administration |
| FARS | Fatal Accident Reporting System |
| FAST | Final Approach Spacing Tool |
| FBI | Federal Bureau of Investigation |
| FedEx | Federal Express |
| FHWA | Federal Highway Administration |
| FMC | Federal Maritime Commission |
| FMCSA | Federal Motor Carrier Safety Administration |
| FRA | Federal Railroad Administration |
| FTA | Federal Transit Administration |
| GAIN | Global Aviation Information Network |
| GAMA | General Aviation Manufacturers Association |
| GARA | General Aviation Revitalization Act |
| GDP | Gross Domestic Product |
| GEO | Geostationary Earth Orbit |
| GES | General Estimates System |
| GMDSS | Global Maritime Distress and Safety System |
| GNP | Gross National Product |
| GPRA | Government Performance and Results Act of 1993 |
| GPS | Global Positioning System |
| GPWS | Ground Proximity Warning System |
| GWP | Gross World Product |
| VHFCs | Hydrofluorocarbons |
| HOV | High occupancy vehicle |
| HTF | Highway Trust Fund |
| VHSIS | Highway Safety Information System |
| VHSR | Incremental High-Speed Rail |
| IASA | International Aviation Safety Assessment |
| VIATA | International Air Transport Association |
| ICAO | International Civil Aviation Organization |
| ICC | Interstate Commerce Commission |
| IHS | Interstate Highway System |
| IMO | International Maritime Organization |
| ISTEA | Intermodal Surface Transportation Efficiency Act |
| ITS | Intelligent Transportation Systems |
| IVHS | Intelligent Vehicle Highway System |
| IVI | Intelligent Vehicle Initiative |
| LAAS | Local Area Augmentation System |
| LCD | Liquid Crystal Display |
| LEO | Low Earth Orbit |
| LNG | Liquefied Natural Gas |
| LPG | Liquefied Petroleum Gas |
| LTL | Less Than Truckload |
| LTVs | Light trucks and vans |
| Maglev | Magnetic levitation |
| MARAD | Maritime Administration |
| MERCOSUR | Southern Common Market |
| mmbd | Million barrels of oil per day |
| mph | Miles per hour |
| MPO | Metropolitan Planning Organization |
| MSP | Maritime Security Program |
| MTMCTEA | Military Traffic Management Command Transportation Engineering Agency |
| MTS | Marine Transportation System |
| N2O | Nitrous Oxide |
| NAFTA | North American Free Trade Agreement |
| NAS | National Airspace System |
| NASA | National Aeronautics and Space Administration |
| NHS | National Highway System |
| NCP | National Contingency Plan |
| NDGPS | Nationwide Differential Global Positioning System |
| NDRF | National Defense Reserve Fleet |
| NEPA | National Environmental Policy Act |
| New | HSR new high-speed rail systems |
| NGS | National Geodetic Survey |
| NHS | National Highway System |
| NHTSA | National Highway Traffic Safety Administration |
| NIMBY | not in my back yard |
| NMMA | National Marine Manufacturers Association |
| NMSL | National Maximum Speed Limit |
| NO2 | nitrogen dioxide |
| NOAA | National Oceanic and Atmospheric Agencys |
| NOTAM | Notices to Airmen |
| NOx | nitrogen oxide |
| NPTS | Nationwide Personal Transportation Survey |
| NS | Norfolk Southern |
| NSC | National Security Council |
| NSI | National Shipbuilding Initiative |
| NTSB | National Transportation Safety Board |
| NUMMI | New United Motor Manufacturing, Inc. |
| O3 | ozone |
| OPEC | Organization of Petroleum Exporting Countries |
| OSRA | Ocean Shipping Reform Act |
| OTRBs | over-the-road buses |
| PanAm | Pan American |
| Pb | lead |
| PCBs | polychlorinated biphenyl |
| PDDs | Presidential Decision Directives |
| PFCs | Perfluorocarbons |
| PM10 | particulate matter less than 10 microns |
| PNGV | U.S. Partnership for a New Generation of Vehicles |
| ppm | parts per million |
| PPPs | Power Projection Platforms |
| PTC | Positive Train Control |
| PTP | Prevention Through People |
| R&D | research and development |
| RNAV | Area Navigation |
| RPM | Revenue Passenger Miles |
| RRF | Ready Reserve Force |
| RRIF | Railroad Rehabilitation and Improvement Financing |
| RSPA | Research and Special Programs Administration |
| RTMs | revenue ton-miles |
| SA | Selective Availability |
| SAFER | Special Aviation Fire and Explosion Reduction |
| SCADA | Supervisory Control And Data Acquisition |
| SEABEE | Construction Battalion (CB)-this acronym is a Phonetic reference to the CB member of this Navy Unit. |
| SF6 | Sulfur Hexafluoride |
| SIPs | Safety Integration Plans |
| SIPs | State Implementation Plans |
| SO2 | sulfur dioxide |
| SPEARS | Screener Proficiency Evaluation and Reporting System |
| STARS | Standard Terminal Automation Replacement System |
| VSTB | Surface Transportation Board |
| STRAHNET | Strategic Highway Network |
| SUVs | sport utility vehicles |
| TCAS | Traffic Alert Collision Avoidance System |
| TDM | Transportation Demand Management |
| TDLS | Tower Data Link Services |
| TEA-21 | Transportation Efficiency Act for the 21st Century |
| TEU | 20-foot equivalent unit |
| TIFIA | Transportation Infrastructure Finance and Innovation Act of 1998 |
| TIP | Threat Image Projection |
| Title XI | Maritime Guarantee |
| TL | Truckload |
| TRACON | Terminal Radar Approach Control |
| TTI | Texas Transportation Institute |
| TWA | Trans World Airlines |
| TWA | Trans World Airlines |
| UNFCCC | United Nations Framework Convention on Climate Change |
| UPS | United Parcel Service |
| USCG | U.S. Coast Guard |
| USDOC | U.S. Department of Commerce |
| USDOT | U.S. Department of Transportation |
| USGS | U.S. Geological Survey |
| USPS | U.S. Postal Service |
| UST | Underground Storage Tank |
| UTA | Union de Transport Aeriens |
| VHF | Very High Frequency |
| VISA | Voluntary Intermodal Sealift Agreement |
| VLCCs | very large crude carriers |
| VMT | vehicle-miles traveled |
| VOCs | volatile organic compounds |
| VSL | variable speed limit |
| WAAS | Wide Area Augmentation System |
| WRDA | Water Resources Development Act |