PIIN
| Acronym | Definition |
|---|---|
| PIIN | Phase-Induced Intensity Noise |
| PIIN | Procurement Instrument Identification Number |
| PIIN | Pittsburgh Interfaith Impact Network (Pittsburgh, PA) |
| PIIN | Procurement Item Identification Number |
| PIIN | Police Integrated Information Network (Philadelphia, Pennsylvania) |
| PIIN | Procurement Instrument/Instruction Identification Number |