| Abbreviation | Definition |
|---|---|
| NRG | National Research Group |
| NRI | Non Registered Indian |
| NRLCA | National Rural Letter Carriers' Association |
| NRM | National Risk Management |
| NRM | Natural Resources Management |
| NRO | National Registration Organization |
| NRODT | National Review on Dead Tree |
| NROL | National Reconnaissance Office Launch |
| NRR | NRC Office of Nuclear Reactor Regulation |
| NRRI | National Retirement Risk Index |
| NRRM | Nuclear Risk Reduction Measure |
| NRRZ | National Reources Re-Zoning |
| NRS | National Regulatory Services |
| NRS | National Relay Services |
| NRTC | National Radio Telecommunication Corporation |
| NRTL | Nationally Recognized Testing Laboratory |
| NRTS | National Reactor Testing Station |
| NRU | Natural Resources Uses Subcommittee |
| NS | National Service |
| NS | Non Specific |