| Abbreviation | Definition |
|---|---|
| ARF | Animal Rescue Fund |
| ARFFC | Alzheimer's Research Foundation, Fisher Center |
| ARGH | Association de Ringuette Gatineau-Hull |
| ARGH | Autism Rights Group Highland |
| ARI | Africa Research Institute |
| ARI | Asian Relief, Inc. |
| ARIS | Aids Resources Information And Services |
| ARL | America Responds with Love |
| ARL | Animal Rescue League |
| ARM | Alliance for Regenerative Medicine |
| ARME | Animal Rescue Media Education |
| ARMS | Asian Relief and Medical Services |
| ARMS | Association for Repetitive Motion Syndromes |
| ARNI | Adoption Resource Network, Inc. |
| ARNI | Animal Rescue Need Intervention |
| ARO | Agriculture Reserarch Organisation |
| ARRG | Amateur Radio Relay Group |
| ARRS | American Roentgen Ray Society |
| ARWL | America Responds With Love |
| AS | Anatomical Society |