| Abbreviation | Definition |
|---|---|
| ABNSOTBD | Airborne and Special Operations Test Board |
| ABO | Agent of Biological Origin |
| ABO | Air Base Operability |
| ABO | Army Budget Office |
| ABO | Blood types A, B, and O Blood Typing System |
| ABOIP | Amended Basis of Issue Plan |
| ABP | Air Battle Plan |
| ABPO | Advanced Base Post Office |
| ABPS | Automated Barrier Plan System |
| ABR | Airborne Radar |
| ABRAMS | Antibomb Rocket and Mortar System |
| ABRDL | Army Biomedical Research & Development Laboratory |
| ABRES | Advanced Ballistic Reentry System |
| ABRES | Advanced Ballistic Reentry Systems |
| ABRO | Army Base Repair Organisation |
| ABRO | Army Base Repair Organisation (UK) |
| ABS | Able Bodied Seaman |
| ABS | Absent |
| ABS | Action Battle System |
| ABS | Advanced Battle Simulation |