"A",
"B",
"C",
"D",
"E",
"F",
"G",
"H",
"I",
"J",
"K",
"L",
"M",
"N",
"O",
"P",
"Q",
"R",
"S",
"T",
"U",
"V",
"W",
"X",
"Y",
"Z"
'Oa' to 'Om', 'On' to 'Oz'
| O&M | - | operations and maintenance |
| OBDII | - | On-Board Diagnostics II Bus [OBDII Bus], [OBDII Terms] |
| OC | - | Open Collector [Transistor Manufacturers] |
| OC | - | operations center |
| OC1 | - | Optical Carrier, Level 1 |
| OCC | - | Other Common Carrier |
| OCR | - | Optical Character Reader |
| OCR | - | optical character recognition |
| OCU | - | Orderwire Control Unit |
| OCUR | - | OpenCable Unidirectional Receiver |
| OCVCXO | - | Oven controlled-voltage controlled crystal oscillator |
| OCXO | - | oven controlled crystal oscillator [OC Manufacturers] |
| OD | - | Optical Density |
| OD | - | Outside Diameter |
| ODD | - | Optical Disk Drive |
| ODI | - | Open Data-link Interface |
| ODU | - | Optical channel Data Unit |
| OEM | - | Original Equipment Manufacturer [List of Manufacturers] |
| OFC | - | Optical Fiber Conductive |
| OFCC | - | Optical Fiber Cable Component |
| OFCP | - | Optical Fiber Conductive Plenum |
| OFCR | - | Optical Fiber Conductive Riser |
| OFN | - | Optical Fiber Nonconductive |
| OFNP | - | Optical Fiber Nonconductive Plenum |
| OFNR | - | Optical Fiber Non-conductive Riser |
| OH | - | Overhead |
| OLED | - | Organic light-emitting diode [Displays] |
| OLT | - | Optical Line Terminal |
| OMB | - | Office of Management and Budget |
Next set of "O" Acronyms, Abbreviations
