| OE | on examination; order entry [system]; orofacial cleft; orthopedic examination; otitis externa; out-s... |
|---|---|
| OH | hydroxycorticosteroid; obstructive hypopnea; occipital horn; occupational health; occupational histo... |
| OHCA | out-of-hospital cardiac arrest |
| OOB | out of bed |
| OOH | out-of-hospital |