| Abbreviation | Definition |
|---|---|
| OCE | Optical Control Electronics |
| OCF | Onboard Computational Facility |
| OCF | Orbiter Computational Facility |
| OCGF | Organic Crystal Growth Laboratory Facility |
| OCH | Orbiter Common Hardware |
| OCM | Organic Content Monitor |
| OCN | Order Control Number |
| OCO | OMS (Orbital Maneuvering System) CutOff |
| OCO | OMS Cutoff |
| OCO | Open-Close-Open |
| OCP | Output Control Pulse |
| OCRM | Orbiter Crash and Rescue Manuals |
| OCS | Onboard Checkout System |
| OCS | Optical Control System |
| OCT | Octal |
| OD | Operational Downlink |
| OD | Operations Directive |
| OD | Orbit Determination |
| OD | Outside Diameter |
| OD | Oxygen Drain |