| Abbreviation | Definition |
|---|---|
| AAPM | American Association of Physicists in Medicine |
| AAPS | American Association of Pharmaceutical Scientists |
| AARP | American Association of Retired Persons |
| AASA | Aging and Adult Services Administration |
| AASP | American Association of Swine Practitioners |
| AASRP | American Association of Small Ruminant Practitioners |
| AATB | American Association of Tissue Banks |
| AAVLD | American Association of Veterinary Laboratory Diagnosticians |
| AAVMC | Association of American Veterinary Medical Colleges |
| AB | Analysis Branch |
| AB(CDRH) | Analysis Branch (CDRH) |
| ABC | American Blood Commission |
| ABC | America's Blood Centers |
| ABCS | Active Bacterial Core Surveillance |
| ABE | Adverse Biologic Experience |
| ABG | Arterial Blood Gas |
| ABI | Automated Broker Interface |
| Abifarma | Brazilian Association of the Pharmaceutical Industry |
| ABLES | Adult Blood Level Epidemiology Surveillance |
| ABLES | Adult Blood Level Epidemiology & Surveillance |