| A&T | Acquisition and Technology 
| Others |
| A&T | Architecture and Transport
| Others |
| A&T | Automotive and Transportation
| Others |
| A&T | Ayo & Teo
| Others |
| A&T | North Carolina Agricultural & Technical State University
| Others |
| A/T | According To
| Others |
| A/T | Autothrottle
| Others |
| AT | Abnormal Tread wear
| Others |
| AT | Absolute Terror
| Others |
| AT | Acceleration Therapeutics
| Others |
| AT | Acceptance Test
| Others |
| AT | Acceptance Testing
| Others |
| AT | Access Terminal
| Others |
| AT | Access Time
| Others |
| AT | Access Type
| Others |
| AT | Accessible Technology
| Others |
| AT | Achilles tendon
| Others |
| AT | Acquisition Team
| Others |
| AT | Acquisitions Team
| Others |
| AT | Action Tremor
| Others |
| AT | Active Terminator
| Others |
| AT | Active Transport
| Others |
| AT | Active Treatment
| Others |
| AT | Acute Thrombosis
| Others |
| AT | Acute Tonsillitis
| Others |
| AT | acyltransferase
| Others |
| AT | Addis Tribune
| Others |
| AT | Additive Templates
| Others |
| AT | Adenine and Thymine
| Others |
| AT | Adenine-Thymine
| Others |
| AT | Adenomatoid Tumour
| Others |
| AT | adenotonsillectomy
| Others |
| AT | Adhesive Transfer
| Others |
| AT | Administration Technician
| Others |
| AT | Adoptive Transfer
| Others |
| AT | Advanced Technologies Intelligent Vision Conference
| Others |
| AT | Advanced Technology
| Others |
| AT | Adventure Time
| Others |
| AT | Aerobic Training
| Others |
| AT | Affine Transform
| Others |
| AT | After Tax
| Others |
| AT | Agent Team
| Others |
| AT | Agglutination Test
| Others |
| AT | Agile and Transparent
| Others |
| AT | Agreement Time
| Others |
| AT | Air Temperature
| Others |
| AT | Air Traffic
| Others |
| AT | Air Transport
| Others |
| AT | Air Trapping
| Others |
| AT | Aircraft Tools
| Others |
| AT | Aircraft Transport
| Others |
| AT | Airtel Tanzania
| Others |
| AT | Alert Time
| Others |
| AT | Alkaline Transition
| Others |
| AT | All Terrain
| Others |
| AT | All That
| Others |
| AT | All Times
| Others |
| AT | Alopecia Totalis
| Others |
| AT | Alpine Touring
| Others |
| AT | Alt.Tasteless
| Others |
| AT | Alternate Thread
| Others |
| AT | Alternative Therapy
| Others |
| AT | Alternative Thread
| Others |
| AT | Altes Testament
| Others |
| AT | Ambient Temperature
| Others |
| AT | American Trails
| Others |
| AT | Anaerobic Threshold
| Others |
| AT | Angular Timer
| Others |
| AT | Animal Tusk
| Others |
| AT | Annual Training
| Others |
| AT | Anterior Temporal
| Others |
| AT | Anterior Tibial
| Others |
| AT | Anti T
| Others |
| AT | Anti-Tank
| Others |
| AT | Anti-Terrorism
| Others |
| AT | Anti-Terrorist
| Others |
| AT | Antiterrorism
| Others |
| AT | AntiThrombin
| Others |
| AT | antitrypsin
| Others |
| AT | Appeal Tribunal
| Others |
| AT | Arabidopsis Thaliana
| Others |
| AT | Arambai Tenggol
| Others |
| AT | Army Transformation
| Others |
| AT | Army Troops
| Others |
| AT | Army Truck
| Others |
| AT | Arranged Team
| Others |
| AT | Art Trade
| Others |
| AT | Arterial Tension
| Others |
| AT | Arterial Thrombosis
| Others |
| AT | Arthur Tom
| Others |
| AT | Assay Technologies
| Others |
| AT | Assistant Technician
| Others |
| AT | Assistive Technology
| Others |
| AT | Astatine
| Element |
| AT | Asti (Provence)
| Others |
| AT | At At
| Others |
| AT | Ataxia Telangiectasia
| Others |
| AT | Athletic Trainer
| Others |
| AT | Atlanta Field Office
| Others |
| AT | Atlantic Time
| Measurement Unit, Time, Time Zone |
| AT | Atrial Tachyarrhythmia
| Others |
| AT | Atrial Tachycardia
| Others |
| AT | Atrophic Thyroiditis
| Others |
| AT | Attention
| Others |
| AT | ATtention command
| Others |
| AT | Attention To ....
| Others |
| AT | Augmented Reality
| Others |
| AT | Austria
| Others |
| at | Austria (TLD)
| Others |
| AT | Auto Train
| Others |
| AT | Autogenic Training
| Others |
| AT | Autoimmune Thrombocytopenia
| Others |
| AT | Autologous Transfusion
| Others |
| AT | Autologous Transplantation
| Others |
| AT | Automatic Tension
| Others |
| AT | Automatic Transfer
| Others |
| AT | Automatic Transmission
| Others |
| AT | Available Time
| Others |
| AT | Average Transaction
| Others |
| AT | Avrupa Toplulugu
| Others |
| AT | Awkward Turtle
| Others |
| AT | Axillary Temperature
| Others |
| At | Total Attainable Search Area
| Others |
| AT | Tug (Auxiliary, Tug)
| Others |
| AT% | Atomic Percent
| Others |