| ON | occipitonuchal; office nurse; onlay; optic nerve; orthopedic nurse; osteonecrosis; osteonectin; overnight |
|---|---|
| ONC | oncogene; oncology; Orthopaedic Nursing Certificate; over-the-needle catheter |
| OND | Ophthalmic Nursing Diploma; orbitonasal dislocation; other neurological disorders |
| ONG | optic nerve glioma |
| ONMRS | onychotrichodysplasia-neutropenia-mental retardation syndrome |
| ONP | operating nursing procedure; orthonitrophenyl |
| ONPG | o-nitrophenyl-beta-D-galactopyranoside |
| ONS | Oncology Nursing Society |
| ONTG | oral nitroglycerin |
| ONTR | orders not to resuscitate |