| OS | left eye [Lat. oculus sinister]; occipitosacral; occupational safety; office surgery; Omenn syndrome... |
|---|---|
| OSM | ovine submaxillary mucin; oxygen saturation meter |
| P-50 | oxygen half-saturation pressure |
| PS | pacemaker syndrome; paired stimulation; paradoxical sleep; paraspinal; parasympathetic; Parkinson sy... |
| rSO2 | regional oxygen saturation |