| Acronym | Definition |
|---|
| ORTT➣Országos Rádió És Televízió Testület (Hungarian: National Radio and Television Authority; Budapest, Hungary) |
| ORTT➣Operations Room Team Trainer (Royal Canadian Navy) |
| ORTT➣Outward Remittance Telegraphic Transfer (HSBC Bank; Hong Kong) |
| ORTT➣Off Road Trail Tools (Tucson, AZ) |
| ORTT➣Order of Repeatermen and Toll Testboardmen (telephone industry union) |
| ORTT➣Operational Readiness Training Test |