| Abbreviation | Definition |
|---|---|
| QLD | Quad-Level Dimmer switch |
| QLD/FC | Quad-Level Dimmer/Flicker Controller |
| QLL | Quasi-Liquid Layer |
| QLNA | Quadrature Low-Noise Amplifier |
| QML | Qualified Manufacturers List |
| QMM | Quick Mix Mike |
| QMS | Quadra Mono Sonic |
| QMS | Quadrupole Mass Spectroscopy |
| QOB | Quick Open Bolted circuit breaker |
| QOB | Quick Opening Breaker |
| QOUT | Charge going OUT |
| QP | Qualified Product |
| QP | Quick Panel |
| QPC | Quantum Point Contact |
| QPE | Quiet Personal Electronics |
| QPF | Quadruple Point Failure |
| QPH | Quartz Process Heater |
| QPJ | Quick Panel Jumper |
| QPL | Qualified Products List |
| QPSK | Quadrature Phase Shift Keying |