| Acronym | Definition |
|---|
| AAT | Association of Accounting Technicians |
| AAT | Administrative Appeals Tribunal |
| AAT | Animal-Assisted Therapy |
| AAT | Alpha-1-Antitrypsin |
| AAT | Anglo Australian Telescope (Anglo-Australian Observatory, Sliding Spring, Australia) |
| AAT | Australian Antarctic Territory |
| AAT | Art & Architecture Thesaurus (Getty) |
| AAT | Alanine Aminotransferase |
| AAT | Aquatic Ape Theory (paleoanthrological hypothesis: aka AAH) |
| AAT | Armored Assault Tank (Star Wars) |
| AAT | Average Access Time |
| AAT | AutoAlliance Thailand |
| AAT | And Another Thing |
| AAT | Ambient Air Temperature |
| AAT | American Accent Training |
| AAT | Airports Authority of Thailand |
| AAT | Associate in Arts in Teaching |
| AAT | Armored Attack Tank (Star Wars) |
| AAT | African Animal Trypanosomiasis |
| AAT | Action on Alcohol and Teens |
| AAT | Advanced Antenna Technology |
| AAT | Advanced Algebra Trigonometry |
| AAT | Allo Anjou Taxi (French taxi service) |
| AAT | Average Annual Temperature (climate statistic) |
| AAT | Activity As Tolerated (medical) |
| AAT | Automatic Atrial Tachycardia |
| AAT | Atomic Axial Tensor |
| AAT | Achievement and Attainment Table |
| AAT | Asbestos Awareness Training |
| AAT | Army Assault Team |
| AAT | Avis d'Arrêt de Travail (French: Stop Work Notice) |
| AAT | Aviation Advisory Team |
| AAT | Aviation Applied Technology |
| AAT | Anti-Aircraft Turret |
| AAT | Animal-Aided-Therapy |
| AAT | Architecture Analysis Tool |
| AAT | Availability Analysis Tool |
| AAT | ATO/ACO Tool |
| AAT | Automatic Analog Tester |
| AAT | Advanced Analytic Tools |
| AAT | Advanced Armament Technology |
| AAT | Approach Avoidance Theory |
| AAT | Acceptability Advisory Team |
| AAT | Allowed Alternative Treatment (Singapore) |
| AAT | Australian Accommodated Tours |
| AAT | Anomaly Analysis Team |
| AAT | Asbestos Abatement Team |
| AAT | Address Allocation Table |
| AAT | Alliance Against Terrorism |
| AAT | Aseite Austria Tischler |
| AAT | Advanced Audit Technique |
| AAT | Advanced ATM Technology (Sprint) |
| AAT | Azur Affrètement Transports (French transportation company) |
| AAT | AWSIM (Air Warfare Simulation Model) Analysis Tool (US DoD) |
| AAT | Associated Actors and Technicians (Weber State University; Ogden, UT) |