| Action Tracking Register | Academic & Science |
| Adaptive Temporal Recursion | Academic & Science |
| AutoThermal Reforming | Academic & Science |
| Absolute Time Reference | Academic & Science |
| Advanced Test Reactor | Academic & Science |
| Atar | Airport Code |
| Acid Test Ratio | Banking |
| Auto Parts Ring | Business |
| Aptar Group, Inc. | Business |
| Automatic Tampon Remover | Business |
| Avion de Transport Regional | Business |
| Accuracy Timeliness Responsiveness | Business |
| Advanced Technologies and Research | Business |
| Aerei da Trasporto Regionale | Business |
| Astron Corporation, Limited | Business |
| Accounting to Reporting | Business |
| Atari Teenage Riot | Community |
| All That Remains | Community |
| Absent Teacher Reserve | Community |
| African Traditional Religion | Community |
| Answer To Reset | Computer Assembly Language |
| Acceptance Test Review | Computing |
| Adaptive Transformation | Computing |
| Automatic Terminal Recognition | Computing |
| Apollo Token Ring | Computing |
| Audio Tape Recorder | Computing |
| Alternate Trunk Routing | Computing |
| Alexa Traffic Rank | Computing |
| All Terrain Racing | Computing |
| Andy's Techno Rules | Computing |
| Antenna Test Range | Electronics |
| Attenuated Total Reflectance | Electronics |
| Alpha Test Realm | General |
| Advanced Term Registration | General |
| Abe T Rosenthal | General |
| Auto Transformer Rectifier | General |
| Accumulated Time Record | General |
| and the Role | General |
| All Terrain Road | General |
| Arkansas Trucking Report | General |
| Automobiles Transport Rapide | General |
| Autoliv Turkey | General |
| Average Treatment Rate | General |
| Automated Target Recognition | General |
| Automated Traffic Recorder | General |
| Active Time Report | General |
| AGS to RHIC | General |
| Aviation Training Relocation | General |
| Acceptance Test Report | General |
| Assess Transform Reach | General |
| Attenuated Total Reflection | General |
| Accommodated Test Request | General |
| Arena Technical Resources | General |
| Articulated Tail Rotor | General |
| Automatic Locking Retractors | General |
| Amicale du Tracteur Renault | General |
| Automatic Traffic Recorder | General |
| Autotrack | General |
| Automatic Transmission Relay | General |
| Automotive Tradition | General |
| Accord Type R | General |
| Access To Recovery | General |
| Advanced Thermo Resin | General |
| Appropriate Technical Resources | General |
| Transmission Remanufacturing | General |
| Air Transport Rated | General |
| American Technical Resources | General |
| All Things Rock | General |
| Annual Temperature Range | General |
| The Ags To Rhic | General |
| A Tape Reader | General |
| Ataxia Telangiectasia and Rad3 | General |
| Ability to Repay | General |
| All Terrain Rig | General |
| Avions De Transport Regional | Governmental |
| All Terrain Radial tire | Governmental |
| Action Taken Report | Governmental |
| After The Revolution | Governmental |
| Americans for Tax Reform | Income Tax |
| ATTAR | Indian Railway Station |
| Art Therapist Registered | Jobs |
| Arithmetical Transfinite Recursion | Maths |
| Almost Totally Real | Maths |
| Additional Testing Required | Medical |
| Achilles Tendon Reflex | Medical |
| Atrophy | Medical |
| Acute Transfusion Reaction | Medical |
| Automatic Tampon Removal | Medical |
| Advanced Tongue Root | Medical |
| Ataxia Telangiectasia and Rad3 related | Medical |
| Anti Tank Rifle | Military and Defence |
| Attack The Rim | Military and Defence |
| Automatic Target Recognition | Military and Defence |
| Advanced Tactical Radar | Military and Defence |
| Annual Training Requirement | Military and Defence |
| Attrition Reserve | Military and Defence |
| Auxiliary Tug and Rescue | Military and Defence |
| Attack The Radical | Military and Defence |
| Average True Range | Military and Defence |
| All Terrain Rifle | Military and Defence |
| Air Transport Rack | Military and Defence |
| Alaska Trauma Registry | Military and Defence |
| Army Training Regiment | Military and Defence |
| Anglican Theological Review | News & Entertainment |
| Avions Transport Regional | Regional |
| Alliance Terminal Railroad | Regional |
| Above The Rest | Space Science |
| Advanced Technology Recycling | Sports |
| Australian Tournament Rankings | Sports |
| Automatic Ticket Resolution | Sports |
| Adventure Tour Race | Sports |
| Average Trading Range | Stock Exchange |
| Albemarles Technology Resource | Technology |
| Advanced Technology and Research | Technology |
| Advanced Telecommunications Research | Telecommunication |
| Andaman Trunk Road | Transport & Travel |
| Atar Airport | Transport & Travel |
| Atractyloside | Trees & Plants |
| Avions De Transport R | Uncategorized |
