| AA | abdominal aorta; acetic acid; achievement age; active alcoholic; active assistive [range of motion];... |
|---|---|
| HLA | histocompatibility leukocyte antigen; histocompatibility locus antigen; homologous leukocyte antibod... |
| AU | according to custom [Lat. ad usum]; allergenic unit; ngstrom unit; antitoxin unit; arbitrary unit; A... |
| Au | Australia [antigen]; authorization; gold [Lat. aurum] |
| Au | Ag Australia antigen |