| PLR | pupillary light reflex |
|---|---|
| PLV | partial liquid ventilation; poliomyelitis live vaccine; panleukopenia virus; phenylalanine, lysine, ... |
| QLS | Quality of Life Scale; quasielastic light-scattering spectroscopy |
| UVL | ultraviolet light |
| WLM | white light microscopy; working level month [radon] |