| OASI | Old Age and Survivors Insurance |
|---|---|
| OLD | obstructive lung disease; orthochromatic leukodystrophy |
| OMI | office of medical investigator; old myocardial infarction |
| OYE | old yellow enzyme |
| STOP | Study of Hypertension in the Elderly [Sweden] or Swedish Trial in Old Patients with Hypertension; su... |