| Abbreviation | Definition |
|---|---|
| USEB | Used Shop Equipment Bulletin |
| USET | Upper Stage Engine Technology |
| USI | Update Software Identity |
| USICU | United States ISPR (International Standard Payload Rack) Checkout Unit |
| USML | United States Microgravity Laboratory |
| USML-1 | United States Microgravity Laboratory-1 |
| USML-2 | United States Microgravity Laboratory-2 |
| USMP | United States Microgravity Payload |
| USMP | United States Micro-gravity Payload |
| USMP-1 | United States Micro-gravity Payload-1 |
| USMP-2 | United States Micro-gravity Payload-2 |
| USMP-3 | United States Micro-gravity Payload-3 |
| USMP-4 | United States Micro-gravity Payload-4 |
| USNS | United States Navy Ship |
| USO | Ultra Stable Oscillator |
| USOC | User Support and Operations Center |
| USR | User Support Room |
| USRA | Universities Space Research Association |
| USRP | Undergraduate Space Research Participation |
| USRP | Undergraduate Student Research Program |