| Abbreviation | Definition |
|---|---|
| UTG | Universal Time-code Generator |
| UTI | Uchebno-Tretirovochnyy Istrebitel (Russian: Fighter Trainer) |
| UTIC | USAREUR Theater Intelligence Center |
| UTL | Underwater Torpedo League |
| UTM | Unit Training Management |
| UTM | Universal Transverse Mercator |
| UTO | Underground Terror Organization |
| UTO | Unit Table of Organization |
| UTO | Unit Task Organization |
| UTO | Unit Training Operations |
| UTO | United Tajik Opposition |
| UTR | Under The Radar |
| UTR | Underwater Tracking Range |
| UTSS | Universal Threat Simulator System |
| UTV | Uninspected Towing Vessel |
| UU | Unclassified Unlimited |
| UU | User Unit |
| UUM | Underwater-to- Underwater Missile |
| UUM-44 | Subroc missile |
| UUR | Unit Under Review |