| AAB | American Association for Bronchology |
|---|---|
| AAB | Anderson Anderson and Brown |
| AAB | Associação dos Arquivistas Brasileiros |
| AAB | Association of Aircraft Brokers, Združenie sprostredkovateľov v leteckej doprave (angl.skr.) |
| AAC | Airborne Aircraft Controller |
| AAI | Autodesk Approved Instructor |
| AAN | Airborne Aircraft Controller |
| AAN | American Academy of Neurology (skr.) |
| AAP | Alternate Access Provider |
| AAR | Association of American Railroads, Asociácia amerických železničných spoločností (angl.skr.) |