| Abbreviation | Definition |
|---|---|
| INR | International Normalized Ratio |
| INROMS | Gene Stratton Porter Memorial Library, Rome City, Indiana |
| INT | Integer (Whole Number) |
| INV | INVerse |
| INV | Invert |
| IO | Infinitely Often |
| IO | Interpolate Once |
| IOA | Inner Objects Algebra |
| IOC | Iteration On Coefficient |
| IP | Initial Permutation |
| IP | Integer Programming |
| IPAM | Institute For Pure And Applied Mathematics |
| IPD | Inline Progression Dimension |
| IPD | Integral Parameter Differences |
| IPD | Inverse Power Distance |
| IPQ | Inverse Piecewise Quadratic |
| IQR | Inter Quartile Range |
| IQR | interquartile range |
| IR | Irreducible Representation |
| IRI | Inter-Reward Interval |