| Academic Affairs Board | Academic & Science |
| Alumni Association Board | Academic & Science |
| Aberdeen Abbreviated Browser | Academic & Science |
| Associação dos Arquivistas Brasileiros | Academic & Science |
| Association of Brazilian Archivists | Academic & Science |
| Academic Achievement Battery | Academic & Science |
| Associate of Applied Business | Academic & Science |
| Associao dos Arquivistas Brasileiros | Academic & Science |
| Associates Advisory Board | Business |
| Aberdeen International, Inc. | Business |
| Association of Applied Biologists | Business |
| Aloha Alumni Bett | Community |
| Automobile Association of Bangladesh | Community |
| American Academy of Ballet | Community |
| American Association of Bioanalysts | Community |
| Android App Bundle | Computing |
| AAX Token | Cryptocurrency |
| Above and Beyond | General |
| Assessment Appeals Board | General |
| Automatic Airflow Balancing | General |
| Arakawa Auto Body | General |
| All to All Broadcast | General |
| Automotive Association of Brazil | General |
| Asociacion Autodromo Balcarce | General |
| Average At Best | General |
| Autoliv Ab | General |
| Asians At Bain | General |
| Atlantic Auto Brokers | General |
| American Auto Brokers | General |
| Advanced Automotive Batteries | General |
| Avon Auto Brokers | General |
| Acquisition Accession Board | General |
| Android App Bundles | General |
| Alpine Association Bodensee | General |
| Argentina Autoblog | General |
| Acronyms Are Bollocks | General |
| Airfield Administration Building | General |
| Airport Administration Building | General |
| Always A Bridesmaid | General |
| Assault Amphibian Battalion | Governmental |
| Assault Air Bike | Governmental |
| As Amended By | Governmental |
| American Assault Brigade | Governmental |
| American Admiralty Bureau | Governmental |
| Aviation Armament Bulletin | Governmental |
| Architectural Access Board | Governmental |
| Army Air Base | Governmental |
| Anti Aircraft Battery | Governmental |
| Academy of Asian Business | International |
| Asociación de Amigos del Bosque | International |
| Anticlinal Aguada Bandera | International |
| As Always Booring | Internet |
| Asociaci de Amigos del Bosque | Regional |
| All Amateur Basketball | Sports |
| Adjusted At Bats | Sports |
