| Abbreviation | Definition |
|---|---|
| US | Upper Secondary |
| USA | Ultimate Soviet Anihiliation |
| USA | Under Secretary of the Army |
| USA | United States Army |
| USA | United States of America |
| USAA | United States Army Aviation |
| USAAAD | United States Army Air Ambulance Detachment |
| USAABNSOTB | United States Army Airborne and Special Operations Test Board |
| USAAC | United States Army Accessions Command |
| USAAC | United States Army Air Corps |
| USAADASCH | United States Army Air Defense Artillery School |
| USAADBD | United States Army Air Defense Board |
| USAAF | United States Amry Air Force |
| USAAF | United States Army Air Force |
| USAAF | United States Army Air Forces |
| USAARENDB | United States Army Armor and Engineer Board |
| USAARL | United States Army Aeromedical Research Laboratory |
| USAARMC | United States Army Armor Center |
| USAARMS | United States Army Armor School |
| USAAS | United States Army Air Service |