| Abbreviation | Definition |
|---|---|
| A | Adenine |
| A | Alveolization |
| A&P | Anterior and Posterior |
| A&W | Alive and Well |
| A.F. | Amniotic Fluid |
| A/B | Acid/Base ratio |
| A/C | Albumin/Creatinine ratio |
| A/C | Anterior Chamber of eye |
| A/G | Albumin/Globulin ratio |
| A1AD | Alpha-1 Antitrypsin Deficiency |
| A1AD | Alpha-1-Antitrypsin Deficiency |
| A1ATD | Alpha1 Anti-Trypsin Deficiency |
| AA | Abdominal Aorta |
| AA | African-American |
| AA | Alopecia Areata |
| AA | Amino Acid |
| AA | Anal Aneurysm |
| AA | Anatomical Adaptation |
| AA | Aspenice Anesthesiology |
| AA | Of Each |