| ISRR | Indiana Southern Railroad | 印第安纳州南部铁路 |
| ISRR | Internal System Requirements Review | 内部系统要求审查 |
| ISRR | Index of Search and Reunion Resources | 搜索和团圆资源索引 |
| ISRR | International Soundex Reunion Registry | 国际Soundex团聚登记处 |
| ISRR | Indiana Southern Railroad CompanyIncorporated | 印第安纳州南方铁路公司 |