| Abbreviation | Definition |
|---|---|
| ATC | Anatomical Therapeutic Chemical |
| ATE | After The End |
| ATE | At The End |
| ATFL | Advanced Thermo Fluidic Laboratory |
| ATFM | According To Facial Model |
| ATG | Anti-Thymocyte Globulin |
| ATL | Accelerated Technology Laboratories |
| ATL | Accredited Testing Laboratory |
| ATL | Advanced Technologies Laboratories |
| ATL | Aero Tec Laboratories |
| ATLAS | Adjuvant Tamoxifen Longer Against Shorter |
| ATR | Additional Testing Required |
| ATTC | American Type Culture Collection [microbiology] |
| AVA | Anti-Viral Activity |
| AVL | Advanced Visualization Laboratory |
| AVL | Audio Video Laboratories |
| AVL | Autonomous Vehicle Laboratory |
| AVRL | AIDS Vaccine Research Laboratory |
| AWAL | American West Analytical Laboratories |
| AYCT | Active Youth Compound Technology |