| Abbreviation | Definition |
|---|---|
| AED | Automatic External Defibrillator |
| AEFI | Adverse Event Following Immunization |
| AEN | Acute Esophageal Necrosis |
| AEN | Anal Epithelial Neoplasia |
| AEN | Anterior Ethmoidal Nerve |
| AEN | Aseptic Epiphyseal Necrosis |
| AEP | Accredited Exercise Physiologist |
| AEP | Acute Edematous Pancreatitis |
| AEP | Acute Eosinophilic Pneumonia |
| AEP | Acute Experimental Peritonitis |
| AEP | Ampullar Evoked Potential |
| AEP | Auditory Evoked Potential |
| AEP(s) | Alcohol-exposed pregnancy (-ies) |
| AER | Aerosol Liquid |
| AER | Apical Ectodermal Ridge |
| AER | Auditory Evoked Response |
| AERP | Atrial Effective Refractory Period |
| AES | Acute Encephalitis Syndrome |
| AES | Anterior Epidural Space |
| AES | Aortic Ejection Sound |