| T | Therapie |
| T | Teil |
| T3 | Triiodthyronin |
| T4 | Thyroxin |
| TAA | Tachyarrhythmia absoluta |
| TACE | Transarterielle Chemoembolisation |
| TAG | triacylglycerol |
| TAK | Thyreoglobulinantikörper |
| TAPP | Transabdominelle Präperitoneale Plastik |
| TAPVD | totale Fehleinmündung aller Lungenvenen |
| TAR | tiefe anteriore Rectumresektion |
| TAT | Thematischer Apperzeptionstest |
| TAT-Komplex | Thrombin-Antithrombin Komplex |
| TB | Tuberkulose |
| TBA | thyroxin binding albumine |
| tbc | tuberkulös |
| TBG | thyroxine binding globulin |
| TBI | tumor burden index (altern. zu TNM) |
| tbk | tuberkulös |
| Tbl. | Tablette |
| TBMC | Total Bone Mineral Content |
| TBPA | thyroxin binding pre-albumine |
| TBSA | Total Body Surface Area |
| TBVT | tiefe Beinvenenthrombose |
| TCA | tricyclische Antidepressiva |
| TCA | Trichloressigsäure |
| TCCS | Transcranial Color-Coded Duplex Sonography |
| TCD | transkranielle gepulste Dopplersonographie |
| TCF7L2 | transcription factor 7-like 2 |
| TCI | Topische Calcineurin Inhibitor |