| Abbreviation | Definition |
|---|---|
| PGL | Programmable Gain Low |
| PGT | Princeton Gamma Technologies |
| PH | phone |
| PH3 | Phosphine |
| PHA | Pulse Height Analysis |
| PHD | Press Here, Dummy |
| PHEB | Plug in Hybrid Electric Buses |
| PHEEM | PHoto-Electron-Emission Microscopy |
| PHEMT | Pseudomorphic High Electron Mobility Transistor |
| PHES | Pumped Heat Electrical Storage |
| PHP | Personal Handy Phone |
| PHU | Pulse Height Units |
| PHV | PHotoVoltaic |
| PHWG | Process Heater Work Group |
| PHY | Physical Layer |
| PI | Partition Identifier |
| PI | Proportional Integral |
| PI | Pulse Induction |
| PIC | PC Paint image format |
| PIC | Programmable Integrated Circuit |