| OC | obstetrical conjugate; occlusocervical; office call; on call; only child; optic chiasma; oral contra... |
|---|---|
| OCa | ovarian carcinoma |
| OCD | obsessive compulsive disorder; Office of Child Development; Office of Civil Defense; osteochondritis... |
| OGF | ovarian growth factor; oxygen gain factor |
| OHS | obesity hypoventilation syndrome; occipital Horn syndrome; occupational health service; ocular histo... |