- ABAM (Archers And Bowhunters Association Of Manitoba)
- ABAN (Abandonment, (also as AB))
- ABAP (Advanced Business Application Programming)
- ABAS (Aircraft-Based Augmentation System)
- ABAT (AirLand Battle Advanced Technologies)
- ABATE (American Bikers Aimed Towards Education)
- ABB (ASEA Brown Boveri (Swiss-Swedish multinational company))
- ABBA (Agnetha, Benny, Björn, Anni-Frid (Swedish pop group))
- ABBK (Askøy Basketball Klubb)
- ABBL (Austin Blood Bowl League)
- ABBS (Arizona Biological and Biomedical Sciences)
- ABC (Atomic, biological, chemical (replaced by chemical, biological, radiological (CBR), and Nuclear, biological, chemical (NBC)))