| Abbreviation | Definition |
|---|---|
| AOA | Abort Once Around |
| AOA | Abort-Once-Around |
| AOA | Annual Operating Agreement |
| AOCE | Attitude and Orbit Control Electronics |
| AOCMS | Attitude and Orbit Control Measurement System |
| AOCS | Attitude and Orbit Control System |
| AODA | Attitude and Orbit Determination Avionics |
| AOH | Assembly Operations Handbook |
| AOP | Assembly OPerations |
| AOS | Acquisition Of Spaceflight |
| AOSO | Advanced Orbiting Solar Observatory |
| AP | Activity Plans |
| AP | Application Processor |
| AP | Associated Press |
| APAS | Androgynous Peripheral Attachment System |
| APC | Adaptive Payload Carrier |
| APCS | Automated Project Control System (ARTEMIS) |
| APCU | Assembly Power Converter Unit |
| APD | Average Payload Depth |
| APDS | Androgynous Peripheral Docking System |