| Abbreviation | Definition |
|---|---|
| AU | Auto Union |
| AUAM | American Union Against Militarism |
| AUAW | Amalgamated Union of Asphalt Workers |
| AUB | African Union of Broadcasting |
| AUBP | African Union Border Programme |
| AUBS | American Union Benefit Services |
| AUC | Aldan Union Church |
| AUC | Atlantic Union College |
| AUCO | Amalgamated Union of Clothiers Operatives |
| AUCP | All-Union Communist Party |
| AUCU | Auburn University Credit Union |
| AUFC | African Union Finance Commission |
| AUFT | Arab Union of Forensics and Toxicology |
| AUFW | Amalgamated Union of Foundry Workers |
| AUHIP | African Union High Implementation Panel |
| AUIU | Agbarho Urhobo Improvement Union |
| AUJ | Abbottabad Union of Journalists |
| AUJS | Australasian Union of Jewish Students |
| AUPE | Alberta Union of Provincial Employees |
| AURA | Aeronautical Union for Rising Aviation |