| AAB | Associação dos Arquivistas Brasileiros |
|---|---|
| AAS | Approved As Stands |
| ABC | American Broadcasting Company, americká rozhlasová a televízna spoločnosť, televízna stanica v USA |
| ABS | American Bureau of Shipping, spoločnosť klasifikujúca námorné stavby a lode |
| ABS | odstavec (nem.skr.), Absatz (skr.) |
| ADE | Assistant Division Engineer |
| ADI | Advanced Distance Integration |
| AEO | Assistant Executive Officer |
| AES | Advanced Encryption Standard |
| AIN | postava írskej mytológie |