| Abbreviation | Definition |
|---|---|
| A4M | American Academy of Anti-Aging Medicine |
| AA | Académie d'Alsace |
| AA | Académie d'Architecture |
| AA | Academy of Alsace |
| AA | Academy of Architecture |
| AA | Acadmie d'Alsace |
| AA | Acadmie d'Architecture |
| AAA | American Academy of Actuaries |
| AAAAI | American Academy of Allergy, Asthma & Immunology |
| AAAAM | American Academy of Anti-Aging Medicine |
| AAAeIC | Argentine Association of Allergy and Clinical Immunology |
| AAAeIC | Asociacin Argentina de Alergia e Inmunologa Clnica |
| AAAeIC | Asociación Argentina de Alergia e Inmunología Clínica |
| AAAL | American Association for Applied Linguistics |
| AAAS | Alan Alda a Admiration Society |
| AAASS | American Association for the Advancement of Slavic Studies |
| AAB | Associação dos Arquivistas Brasileiros |
| AAB | Associao dos Arquivistas Brasileiros |
| AAB | Association of Brazilian Archivists |
| AABS | Ann Arbor Bonsai Society |