| CEI | character education inquiry; converting enzyme inhibitor |
|---|---|
| OCR | oculocardiac reflex; oculocerebrorenal [syndrome]; optical character recognition |
| OCD | obsessive compulsive disorder; Office of Child Development; Office of Civil Defense; osteochondritis... |
| OCPD | obsessive compulsive personality disorder |
| YBOCS | Yale-Brown Obsessive Compulsive Scale |