| OG | Osmolar Gap; 10 mOsm/kg = measured Osm - calculated Osm |
|---|---|
| OG | obstetrics and gynecology; occlusogingival; oligodendrocyte; optic ganglion; orange green; orogastric |
| OGC | oculogyric crisis |
| OGD | [o]esophago-gastro-duodenoscopy |
| OGDH | oxoglutarate dehydrogenase |
| OGF | ovarian growth factor; oxygen gain factor |
| OGH | ovine growth hormone |
| OGI | oxygen-glucose index |
| OGJ | [o]esophagogastric junction |
| OGS | oxygenic steroid |