| AAD | American Academy of Denturity |
|---|---|
| AAM | Academy of Ancient Music |
| AAN | American Academy of Neurology (skr.) |
| AAN | American Academy of Nursing |
| AAS | Australian Academy of Science |
| AAS | Austrian Academy of Sciences |
| AAT | Army Assault Team |
| AAVA | American Academy of Veterinary Acupuncture (skr.) |
| ABDÓMEN | brucho, zadoček hmyzu (zool.) |
| ABE | Army Background Experiment |