ORN
| Acronym | Definition |
|---|---|
| ORN | Osteoradionecrosis |
| ORN | Omnibusverkehr Rhein-Nahe GmbH (German regional public transport) |
| ORN | Offshoring Research Network (North Carolina) |
| ORN | Olympic Route Network (UK) |
| ORN | Onion Radio News |
| ORN | Operation Rescue National |
| ORN | Oran, Algeria - Es Senia (Airport Code) |
| ORN | Ohio Resource Network (substance abuse) |
| ORN | Outdoor Recreation Network |
| ORN | Obligatory Running Note |
| ORN | Ophthalmic Research Network |
| ORN | Online Racing Network |
| ORN | Original Nutters (gaming clan) |
| ORN | Oval Racing News |