| APA | action potential |
|---|---|
| APAAP | Alkaline Phosphatase anti-Alkaline Phosphatase |
| APACHE | ACUTE PHYSIOLOGY AND CHRONIC HEALTH EVALUATION |
| APACHE II | Acute Physiology And Chronic Health Evaluation |
| APACHE II | Acute Physiology and Chronic Health Evaluation II |
| APAF-1 | Apoptotic protease activating factor-1 |
| APAs | Antiphospholipid antibodies |
| APAS | Antiphospholipid antibody syndrome |
| APase | Alkaline phosphatase |
| APase | acid phosphatase |