| Abbreviation | Definition |
|---|---|
| NTC | (IEEE) (Inter)National Telesystems Conference |
| NVMT | Nonvolatile Memory Technology Conference |
| NZID | Near Zero Interlock Delay |
| OAE | Topical Meeting on Optics in Adverse Environments |
| ODATA | Working Symposium on Oceanographic Data Systems |
| ODS | Topical Meeting on Optical Data Storage |
| OFC | Conference on Optical Fiber Communication |
| OFCIOC | Optical Fiber Communication Conference, and International Conference on Integrated Optics and Optical Fiber Communication |
| OFFICE | IEEE Computer Society Office Automation Symposium |
| OFS | Optical Fiber Sensors Topical Meeting |
| OH | Odd Harmonics |
| OLE | Object Linking and Embedding |
| OMAN | LEOS Summer Topical on Optical Multiple Access Networks |
| OPC | Oscillator Power Control |
| OPGW | Optical Fiber Composite Overhead Ground Wire |
| ORUTA | One Ring to Rule Them All |
| OZCHI | Australian Conference on Computer-Human Interaction |
| PA | IEEE Donald O. Pederson Award in Solid-State Circuits |
| PAC | IEEE Particle Accelerator Conference |
| PACRIM | IEEE Pacific Rim Conference on Communications, Computers, and Signal Processing |