| Acronym | Definition |
|---|
| NIIP➣Net International Investment Position (national finance) |
| NIIP➣Navajo Indian Irrigation Project |
| NIIP➣National Institute of Industrial Psychology |
| NIIP➣Northwest Income Indicators Project (Washington State University) |
| NIIP➣National Information Infrastructure Protection Act of 1996 |
| NIIP➣Negative Inspiratory Intrathoracic Pressure |