| Abbreviation | Definition |
|---|---|
| OUI | Organizationally Unique Identifier |
| OUTWATS | OUTward Wide Area Telecommunications Service |
| OVC | Ohio Valley Cable |
| OVSF | Orthogonal Variable Spreading Factor |
| OXE | OmniPCX Enterprise |
| OYT | Own Your Telephone |
| P/F | Poll/Final Bit |
| PA | Pointer Adjustment |
| PA/VA | Public Address and Voice Alarm |
| PABX | Private Automatic Branch Exchange |
| PAC | Predict Application Control |
| PACTS | Probation and Pretrial Services Automated Tracking System |
| PAD | Packet Assembler / Disassembler |
| PAD | Puzzle And Dragons |
| PAM5 | 5-level (quinary) Pulse Amplitude Modulation |
| PAMD | Plug-in Architecture for Mobile Devices |
| PAMD | Positive Answering Machine Detection |
| PANA | Protocols for carrying Access Network Authentication |
| PASTA | Poisson Arrivals See Time Averages |
| PASTA | Presence Advanced Services for Telco Applications |