| Abbreviation | Definition |
|---|---|
| IRAOS | ,'E9G ,1'-'F 'J1'F |
| IRAOS | Iranian Association of Surgeons |
| IRCS | Indian Red Cross Society |
| IRCS | Ithaca Radio Control Society |
| IRES | International Real Estate Society |
| IRgA | International Reprographic Association |
| IRGO | International Research Group on Ostracoda |
| IRGS | Indian River Genealogical Society |
| IRIAMS | A1GF¯3*'F 9DHE ~24CJ ,EGH1J '3D'EJ 'J1'F |
| IRIAMS | Academy of Medical Sciences of Iran |
| IRIAMS | Islamic Republic of Iran Academy of Medical Sciences |
| IRLOGI | Irish Organisation for Geographic Information |
| IRPS | International Radiation Physics Society |
| IRPS | International Regulatory Peptide Society |
| IRRS | Irish Railway Record Society |
| IRS | Illinois Reading Society |
| IRS | Interesting Readers Society |
| IRS | International Relations Society |
| IRS | International Reynard Society |
| IRS | Irreverent Rodent Society |