| IRN | Consolidated Rail Corporation (formerly Ironton Railroad Company) 
| Others |
| IRN | Illinois Radio Network
| Others |
| IRN | Image reference number
| Others |
| IRN | Implementation Research Network
| Others |
| IRN | Import Release Notice
| Others |
| IRN | Improved RoCE NIC
| Others |
| IRN | In Room Networking
| Others |
| IRN | Inception Radio Network
| Others |
| IRN | Independent Radio News
| Others |
| IRN | Independent Recording Network
| Others |
| IRN | Indian Ring Neck
| Others |
| IRN | Indiana Resource Network
| Others |
| IRN | Individual Record Number
| Others |
| IRN | Information Resource Navigator
| Others |
| IRN | Innovation Reasoning Network
| Others |
| IRN | Inspection Release Note
| Others |
| IRN | Installation Requirement Note
| Others |
| IRN | Institute for Responsible Nutrition
| Others |
| IRN | Institutional Recycling Network
| Others |
| IRN | Intel Research Network
| Others |
| IRN | Intelligent Road Network
| Others |
| IRN | Interface Revision Notice
| Others |
| IRN | Interior Redecorators Network
| Others |
| IRN | Intermediate Routing Node
| Others |
| IRN | Internal Recurrent Neural Network
| Others |
| IRN | Internal Reference Number
| Others |
| IRN | International Radio Network
| Others |
| IRN | International Rally Navigator
| Others |
| IRN | International Referral Network
| Others |
| IRN | International Research Networks
| Others |
| IRN | International Resource Network
| Others |
| IRN | International Rivers Network
| Others |
| IRN | Internet Radio Network
| Others |
| IRN | Internet Resources Newsletter
| Others |
| IRN | Invoice Reference Number
| Others |
| IRN | Ironton Railroad (Conrail)
| Others |
| IRN | The Recycling Network
| Others |