| Abbreviation | Definition |
|---|---|
| ABMSU | All Bodoland Minority Students Union |
| ABMSU | All BTC Minority Students Union |
| ABPU | Agifish Bio Pangasius Union |
| ABU | Arab Beekeepers Union |
| ABWU | All Bengal Women's Union |
| ACCO | Advisory Committee of Commissioned Officers |
| ACCU | America's Christian Credit Union |
| ACCU | Asian Confederation of Credit Unions |
| ACCU | Australian Central Credit Union |
| ACES | Anglo Canada Employees Society |
| ACEU | Air Corporation Employees Union |
| ACFA | Association of Clearing & Forwarding Agents |
| ACFCU | Amarillo Comunity Federal Credit Union |
| ACFCU | Artesian City Federal Credit Union |
| ACIU | Abiriba Communal Improvement Union |
| ACJU | Amalgamated Carpenters and Joiners Union |
| ACLU | American Communist Legal Union |
| ACPA | Air Canada Pilots Association |
| ACPO | Association of Chief of Police Officers |
| ACPU | African Caribbean Produce Union |