| AAA | http://purl.bioontology.org/ontology/MEDLINEPLUS/C0003486 | AAA | |
| AATD | http://purl.bioontology.org/ontology/MEDLINEPLUS/C0221757 | AATD | |
| Abdominal adhesions | http://purl.bioontology.org/ontology/MEDLINEPLUS/C0549357 | Abdominal adhesions | |
| Abdominal Aortic Aneurysm | http://purl.bioontology.org/ontology/MEDLINEPLUS/C0162871 | Abdominal Aortic Aneurysm | |
| Abdominal Pain | http://purl.bioontology.org/ontology/MEDLINEPLUS/C0000737 | Bellyache | |
| Abdominal pregnancy | http://purl.bioontology.org/ontology/MEDLINEPLUS/C0032984 | Abdominal Pregnancy | |
| Abdominal Pregnancy | http://purl.bioontology.org/ontology/MEDLINEPLUS/C0032984 | Abdominal Pregnancy | |
| Abnormalities | http://purl.bioontology.org/ontology/MEDLINEPLUS/C0000768 | Abnormalities | |
| ABO Blood Groups | http://purl.bioontology.org/ontology/MEDLINEPLUS/C0000778 | ABO Blood Groups | |
| Abortion | http://purl.bioontology.org/ontology/MEDLINEPLUS/C0392535 | Abortion | |
| About Your Medicines | http://purl.bioontology.org/ontology/MEDLINEPLUS/C1456676 | About Your Medicines | |
| ABPA | http://purl.bioontology.org/ontology/MEDLINEPLUS/C0004031 | Allergic Bronchopulmonary Aspergillosis | |
| Abscess | http://purl.bioontology.org/ontology/MEDLINEPLUS/C0000833 | Abscess | |
| Abuse | http://purl.bioontology.org/ontology/MEDLINEPLUS/C0562381 | Abuse | |
| Accident prevention | http://purl.bioontology.org/ontology/MEDLINEPLUS/C0000918 | Accident Prevention | |
| Accident Prevention | http://purl.bioontology.org/ontology/MEDLINEPLUS/C0000918 | Accident Prevention | |
| Accidents | http://purl.bioontology.org/ontology/MEDLINEPLUS/C0000924 | Accidents | |
| Achalasia | http://purl.bioontology.org/ontology/MEDLINEPLUS/C0014848 | Achalasia | |
| Achilles Tendon Injuries | http://purl.bioontology.org/ontology/MEDLINEPLUS/C0495953 | Achilles Tendon Injuries | |
| Achondroplasia | http://purl.bioontology.org/ontology/MEDLINEPLUS/C0001080 | Achondroplasia | |
| Acid indigestion | http://purl.bioontology.org/ontology/MEDLINEPLUS/C0235304 | Acid indigestion | |
| Acid Reflux | http://purl.bioontology.org/ontology/MEDLINEPLUS/C0017168 | Acid Reflux | |
| ACL Injuries | http://purl.bioontology.org/ontology/MEDLINEPLUS/C1456574 | ACL Injuries | |
| Acne | http://purl.bioontology.org/ontology/MEDLINEPLUS/C0702166 | Zits | |
| Acne inverse | http://purl.bioontology.org/ontology/MEDLINEPLUS/C0162836 | Acne inverse | |
| Acne rosacea | http://purl.bioontology.org/ontology/MEDLINEPLUS/C0035854 | Acne Rosacea | |
| Acne Rosacea | http://purl.bioontology.org/ontology/MEDLINEPLUS/C0035854 | Acne Rosacea | |
| Acoustic neurilemmoma | http://purl.bioontology.org/ontology/MEDLINEPLUS/C0027859 | Neuroma, Acoustic | |
| Acoustic neurinoma | http://purl.bioontology.org/ontology/MEDLINEPLUS/C0027859 | Neuroma, Acoustic | |
| Acoustic Neuroma | http://purl.bioontology.org/ontology/MEDLINEPLUS/C0027859 | Neuroma, Acoustic | |