| non-REM | non-rapid eye movement [sleep] |
|---|---|
| NREM | nonrapid eye movement [sleep] |
| OD | Doctor of Optometry; obtained absorbance; occipital dysplasia; occupational dermatitis; occupational... |
| ol | left eye [Lat. oculus laevus] |
| OS | left eye [Lat. oculus sinister]; occipitosacral; occupational safety; office surgery; Omenn syndrome... |