| Abbreviation | Definition |
|---|---|
| IRMT | Institute of Risk Management Tanzania |
| IRN | Institute for Responsible Nutrition |
| IRO | Institute for Research in Ophtalmology |
| IRO | Institution of Railway Operators |
| IROC | Institution Race Of Champions |
| IRP | Institute for Research on Poverty |
| IRP | Institute for Retired Professionals |
| IRPA | Institute for Research and Policy on Acceleration |
| IRPA | Institute For Robotic Process Automation |
| IRPE | Institute for Research on Presidential Elections |
| IRPE | Institute for Retirees in Pursuit of Education |
| IRPE | Institute of Radio Physics and Electronics |
| IRPS | Institute for Regulatory Policy Studies |
| IRR | Institute for Religious Research |
| IRR | Institute of Race Relations |
| IRRA | Institute for Reliability and Risk Analysis |
| IRRA | Institute of Russian Realist Art |
| IRRAD | Institute Of Rural Research and Development |
| IRRE | Institute for Research and Reform in Education |
| IRRI | International Renewable Resources Institute |