| Abbreviation | Definition |
|---|---|
| ULSI | Ultra Large Scale Integration |
| ULT | ULTimate |
| ULTDS | Unit-Level Tactical Data Switch |
| UM | Unit Manager |
| UM | Unit of Measure |
| UM | User Manual |
| UMA | Underground Mafias Army |
| UMA | Utah Military Academy |
| UMAP | Utility Military Assistance Program |
| UMC | Union Metallic Cartridge |
| UMC | Unit Movement Coordinator |
| UMC | USAREUR Major Command |
| UMCC | Unit Movement Control Center |
| UMCM | Underwater Mine Countermeasures |
| UMCP | Unit Maintenance Collection Point |
| UMCT | Unit Maintenance Collection Team |
| UMD | Unit Manning Document |
| UMD | Unit Movement Data |
| UMDS | Unsafe Material Data Sheet |
| UME | Ultimate Mercenary Elite |