| Abbreviation | Definition |
|---|---|
| IR | Instrument Reference |
| IR | Intelligence Ratio |
| IRAL | Intelligent Robotics and Automation Laboratory |
| IRAS | infrared reflection absorption spectroscopy |
| IRB | Institutional Review Board |
| IRL | Immunohaematology Reference Laboratory |
| IRP | Interrupted Renewal Process |
| IRRL | Interdisciplinary Robotics Research Laboratory |
| IRT | ImmunoReactive Trypsin |
| ISAAC | ImmunoSpot Array Assay on Chip |
| ISBL | Intelligent Systems and Bioinformatics Laboratory |
| ISBP | International Society for Blood Purification |
| ISBR | In-Situ Bio-Remediation |
| ISBR | Intact Spontaneously Breathing Rat |
| ISBR | International Society for Biosafety Research |
| ISCIII | Instituto de Salud Carlos III |
| ISDL | Integrated System Design Laboratory |
| ISDL | Intelligent System Design Laboratory |
| ISDL | Interactive Systems Design Laboratory |
| ISEL | Intelligent Systems Engineering Laboratory |