| Abbreviation | Definition |
|---|---|
| OCITE | Opto-Coupled Inputs To Ethernet |
| OCR | Optical Character Reader |
| OD | Optical Disk |
| ODA | Open Development Architecture |
| ODBR | Optical Disc Barcode Reader |
| ODC | optical disc cartridge |
| ODC | optical disk cartridge |
| ODDE | Optical Disc Drive Emulators |
| ODM | Original Design Manufacturer |
| ODSS | Optical Data Storage System |
| OE | Operating Environment |
| OE | Output Enable |
| OEE | Overall Equipment Efficiency |
| OEM/OPM | Original Equipment Manufacturer/ ORIGINAL PARTS MANUFACTURER |
| OFC | Optical Fibre Cable |
| OFCC | Optical Fiber Cable Component |
| OHL | Open Hardware Licence |
| OHMP | Oracle Hardware Management Pack |
| OHMS | Open Hardware Management Services |
| OHP | OverHead Projector |