| Abbreviation | Definition |
|---|---|
| NPL | National Priorities List |
| NPMR | North Pacific Marine Research Program |
| NPR | National Performance Review |
| NPTZ | North Pacific Transition Zone |
| NRB | New Research Building |
| NRC | National Reconditioning Order |
| NRC | National Research Council |
| NRC | Nuclear Regulatory Commission |
| NRCDES | National Research Council Division of Earth Sciences |
| NREN | National Research and Education Network |
| NRI | Nationwide Rivers Inventory |
| NRO | National Reconditioning Order |
| NROSS | Navy Remote Ocean Sensing System |
| NRS | Nitrox Rebreather System |
| NRSP | National Remote Sensing Program |
| NRW | Non Revenue Water |
| NS | National academy of sciences |
| NSB | National Science Board |
| NSB | Natural Sea Beauty |
| NSC | National Science Council |