| Acronym | Definition |
|---|
| UDT | Urzad Dozoru Technicznego (Polish: Office of Technical Inspection) |
| UDT | User Defined Type |
| UDT | Underwater Demolition Team (US Navy SEALs) |
| UDT | Undersea Defence Technology (conference) |
| UDT | User Data Type |
| UDT | User Definable Drive Types |
| UDT | Universal Data Transfer |
| UDT | Uniform Data Transfer |
| UDT | Unstructured Data Transfer |
| UDT | User-Defined Table |
| UDT | União Democrática Timorense (Timor Democratic Union, East Timor) |
| UDT | Upper Dublin Township (Pennsylvania) |
| UDT | Uniform Data Transfer (COM-based technologies) |
| UDT | Urine Drug Test |
| UDT | User Data Type (Microsoft) |
| UDT | Undescended Testicles |
| UDT | Uro Dynamic Testing |
| UDT | Utility Dog Tracker (AKC title) |
| UDT | Union des Travailleurs (French: Union Workers) |
| UDT | User Documentation Team (Joomla) |
| UDT | Unit Data Message (SS7) |
| UDT | Unarmed Drill Team |
| UDT | United Dominions Trust Ltd (UK) |
| UDT | Universal Data Translator (modeling and simulation) |
| UDT | Ujian Darjah Tiga (Malaysia) |
| UDT | Under Declaration of Trust |
| UDT | User Defined Tools |
| UDT | Under Deck Tonnage |
| UDT | Underage Drinking Taskforce |
| UDT | Unstructured Data Structure |
| UDT | User Design Team |
| UDT | Uridine Diphosphate-N-Acetylgulucosamine Transferase |
| UDT | U Die Today (gaming clan) |
| UDT | UDP (User Datagram Protocol)-Based Data Transfer (computer networking) |
| UDT | User-Defined Training (certification training) |