| Acronym | Definition |
|---|
| TRN | Toronto (airport code; Toronto, Canada) |
| TRN | Transport |
| TRN | Total Return Net (finance) |
| TRN | Train |
| TRN | Transaction |
| TRN | Technology Research News |
| TRN | Times Record News (Wichita Falls, TX) |
| TRN | Taxpayer Registration Number (Jamaica) |
| TRN | Talk Radio Network |
| TRN | Turnaround |
| TRN | Teaching-Research Nexus |
| TRN | Transparent |
| TRN | Threaded Read News |
| TRN | Terminal |
| TRN | Translation Support File |
| TRN | Transaction Reference Number |
| TRN | Treasury Reserve Note (US Treasury) |
| TRN | Transports Régionaux Neuchâtelois (French; Swiss public transport company) |
| TRN | Trade Name |
| TRN | Token Ring Network |
| TRN | Tax Research Network (UK) |
| TRN | Titre de Reconnaissance de la Nation (French: Full Recognition of the Nation) |
| TRN | Transcriptional Regulatory Network |
| TRN | Temporary Routing Number (telecommunications) |
| TRN | Training Resource Network, Inc |
| TRN | Transit Routing Number |
| TRN | Turin, Italy - Caselle (Airport Code) |
| TRN | Topology Representing Network |
| TRN | Terrain-Reference Navigation |
| TRN | The Radio Network Ltd (New Zealand) |
| TRN | Transition Register |
| TRN | Transaction Register |
| TRN | Training Document (TMINS) |
| TRN | Target Reference Number |
| TRN | Task Requirement Notice |
| TRN | Trashy Romance Novel |
| TRN | Team Rally Nasjonal (Norwegian) |
| TRN | The Rader Network (Colorado Springs, Colorado, USA) |
| TRN | Travel Record Number |
| TRN | The Revellee Nation (non profit organization) |