| Abbreviation | Definition |
|---|---|
| AOQ | Association of Quartermasters |
| AOR | Association of Oregon Recyclers |
| AOR | Association of Reflexologists |
| AORA | Association of Oregon Redevelopment Agencies |
| AORC | Association of Official Racing Chemists |
| AORMA | All Odisha Rice Millers Association |
| AORP | Association of Reentry Professionals |
| AORP | Association of Retired Police |
| AORS | Association of Ontario Road Supervisors |
| AOSA | American Orff Schulwerk Association |
| AOSA | Association of Official Seed Analysts |
| AOTA | American Occupational Therapy Association |
| AOTA | American Organ Transplant Association |
| AOTA | Asia and Oceania Thyroid Association |
| AOTA | Association Of Talented Artists |
| AOTP | Association of Operating Theatre Practitioners |
| AOTS | Association for Overseas Technical Scholarship |
| AOTS | Association of Overseas Technical Scholarship |
| AOVA | Alaska Outdoor Volleyball Association |
| APA | Allied Pilots Association |