sort by Rank | Alpha
| Possible Meanings | Rank |
|---|
| American Orthopaedic Research Society | *** |
| Association of Road Supervisors | *** |
| Automated Order Routing Systems | ** |
| Association of Ontario Road Superintendents | ** |
| Automatic Order Routing System | ** |
| Anarchy Online Reference Site | ** |
| Association of Oak Ridge Scientists | ** |
| Australian Official Radio Service | ** |
| Aviation Occurrence Reporting System | ** |
| Adverse Occurrence Reporting System | * |
| Army Operations Research Society | * |
| AR-PERSCOM Orders and Resource System | * |
| Abnormal Occurrences Reporting System | * |
| AR-PERSCOM Orders Resource System | * |