| CCS | Canadian Cardiovascular Society |
| CCT | kraniale Computertomographie |
| CD | coeliac disease |
| CD | Collum Diaphysen (Winkel) |
| CD | cluster of differentiation (Zelloberflächenantigene) |
| CDA | kongenitale dyserythropoetische Anämie |
| CDAI | Crohn's disease activity index |
| CDC | Center for Disease Control |
| CDC/ CDCA | Chenodesoxycholsäure (Gallensäure von Gänsen) |
| CDE | Rhesus (System) |
| CDK | Cyclin Dependend Kinases |
| CDP | Cytidindiphosphat |
| CDT | Carbohydrate deficient transferrin |
| CDT | Clostridium difficile Toxin |
| CDV | Carotis Druck Versuch |
| CEA | carcino embryonales antigen |
| CED | chronisch entzündliche Darmerkrankungen |
| CEE | zentraleuropäische Enzephalitis |
| CEE | konjugiertes equines östrogen |
| CEP | kongenitale erythropoetische Porphyrie |
| CF | Cystische Fibrose (Mukoviszidose)" |
| CFS | chronique fatigue syndrome |
| CGAP | Cancer Genome Anatomy Project |
| CGIN | Cervikale glanduläre intraepitheliale Neoplasie |
| cGMP | zyklisches Guanosinmonophosphat |
| CGS-System | Grundeinheiten: Zentimeter, Gramm, Sekunde |
| Ch | CharriŠre |
| CHD | KHK (Coronary heart disease) |
| CHD | Congenital heart defect |
| CHE | Cholezystektomie |