| N | Newton |
| N | North |
| N/A | Not Applicable |
| N/O | Normally Open |
| N/S | North/South |
| NAA | Non-Advocate Assessment |
| NAAPS | Navy Aerosol Analysis and Prediction System |
| NAC | National Agency Check |
| NAC | Network Access Control |
| NACI | National Agency Check with Inquiries |
| NACS | NASA Contract Assurance Services |
| NAICS | North American Industrial Classification System |
| NAK | Negative Acknowledgement |
| NAM | National Aviation Meteorologist |
| NAM | North American Mesoscale |
| NAMMA | NASA African Monsoon Multidisciplinary Analyses |
| NAO | NOAA Administrative Order |
| NAR | Non-Advocate Review |
| NAS | Network Attached Storage |
| NASA | National Aeronautics and Space Administration |
| NASCOM | NASA Communications |
| NASTRAN | NASA Structural Analysis |
| NAT | Network Address Translation |
| NAVOCEANO | Naval Oceanographic Office |
| NBAR | Network Based Application Recognition |
| NCAR | National Center for Atmospheric Research |
| NCCM | Network Change and Configuration Management |
| NCDC | National Climatic Data Center (NESDIS) |
| NCEI | National Centers for Environmental Information |
| NCEP | National Center for Environmental Prediction (NWS) |
| NCF | Network Control Facility |
| NCG | Non-Condensable Gas |
| NCIM | Netcool Common Information Model |
| NCIRT | NOAA Computer Incident Response Team |
| NcKL | Netcool Knowledge Library |
| NCOMP | Nighttime Cloud Optical and Microphysical Properties |
| NCWCP | NOAA Center for Weather and Climate Prediction |
| NDA | Non-Disclosure Agreement |
| NDE | Non-Destructive Evaluation |
| NDE | NPOESS Data Exploitation |
| NDI | Non-Destructive Inspection |
| NDI | Non-Development Item |
| NDSI | Normalized Difference Snow Index |
| NDVI | Normalized Difference Vegetation Index |
| NEAR | Near Earth Asteroid Rendezvous |
| NEAR | NSOF Engineering Analysis Room |
| NEC | NOAA Executive Council |
| NEDR | Noise Equivalent Delta Radiance |
| NEDT | Noise Equivalent Delta Temperature |
| NEF | National Essential Function |
| NEII | NESDIS Enterprise Infrastructure Interface |
| NEMA | National Electrical Manufacturers Association |
| NEN | NASA Engineering Network |
| NEN | Near Earth Network |
| NENS | Near Earth Network Services |
| NEP | NOAA Executive Panel |
| NEPA | National Environmental Policy Act |
| NESDIS | National Environmental Satellite, Data and Information Service |
| NESDIS AA | NOAA Assistant Administrator for Satellite and Information Services |
| NET | |
| NetCDF | Network Common Data Form |
| NetMAC | Network Monitor And Control |
| NEXRAD | Next Generation Doppler Radar |
| NF | NASA Form |
| NF | Network Fabric |
| NFDRS | National Fire Danger Rating System |
| NFNMS | NASA’s Foreign National Management System |
| NFOV | Near Field Of View |
| NFS | NASA Federal Acquisition Regulation (FAR) Supplement |
| NFS | Network File System |
| NG/NGR | Northrop Grumman Corp |
| NGDC | National Geophysical Data Center (NESDIS) |
| NGI | Northern Gulf Institute |
| NHC | National Hurricane Center |
| NIC | National Ice Center |
| NIC | Network Interface Card |
| NIDP | Network Intrusion Detection and Protection |
| NIDS | Network Intrusion Detection System |
| NIMO | Networks Integration Management Office |
| NIR | Near Infrared |
| NIRREF | Near Infrared Snow Test |
| NISN | NASA Integrated Services Network |
| NISPOM | National Industrial Security Program Operating Manual |
| NISPP | NESDIS Information Security Program Plan |
| NIST | National Institute of Standards and Technology |
| NIST-SURF | National Institute of Standards and Technologies Synchrotron Ultraviolet Radiation Facility |
| NITF | National Imagery Transmission Format |
| NITRB | NOAA Information Technology (IT) Review Board |
| NLD/LMA | National Lightning Detection/Lightning Mapping Array |
| NLDN | National Lightning Detection Network |
| NLT | No later than |
| NLTZ | No Less than Input Zones |
| N-m | Newton-meter |
| N-m-sec | Newton-meter-second |
| NMAO | NOAA Marine and Aviation Operations |
| Nmax | Percentage of maximum radiance |
| NMFC/JTWC | Naval Maritime Forecast Center/Joint Typhoon Warning Center |
| NMFS | National Maritime & Fisheries Services (NOAA) |
| NOA | New Obligation Authority |
| NOAA | National Oceanic and Atmospheric Administration |
| NOAT | NWS Operational Advisory Team |
| NOC | Network Operations Center |
| NOCC | Network Operations Control Center |
| NODC | National Oceanographic Data Center |
| NODIS | NASA On-Line Directives Information System |
| NOHRSC | National Operational Hydrologic Remote Sensing Center |
| NOI | Notice of Inquiry |
| NOMAT | Non Operational Mission Allowable Temperatures x |
| NON | Negative Orbit Normal |
| NORAD | North American Air Defense Command |
| NOS | National Ocean Service |
| NOSA | National Oceanic and Atmospheric Administration (NOAA) Observing System Architecture |
| NOSC | NOAA Observing System Council |
| NOT | Non-operational Temperatures |
| nPa | Nano Pascals |
| NPD | NASA Policy Directive |
| NPG | |
| NPIV | N-Port ID Virtualization |
| NPOESS | National Polar-Orbiting Environmental Satellite System |
| NPP | NPOESS Preparatory Project |
| NPR | NASA Procedural Requirement(s) |
| NPS | Next-generation Power Supply |
| NPSL | NASA Parts Selection List |
| NRA | NASA Research Announcement |
| NRCS | National Resource Conservation Service |
| NRE | Non-Recurring Engineering |
| NRF | Nominal Reference Frame (defined in GIRD) |
| NRL | Naval Research Lab |
| NRT | Near Real Time |
| NRZ-L | Non-Return-to-Zero-Level |
| NRZ-M | Non-Return-to-Zero-Mark |
| NRZ-S | Non-Return to Zero Space |
| NSA | National Security Agency |
| NSCL | National Superconducting Cyclotron Laboratory (MGH) |
| NSD | Network Shared Disk |
| NSD | Non-SCADA Security Domain |
| NSDS | NASA Software Documentation Standard |
| NSI | NASA Standard Initiator |
| NSI-E | NSI Equivalent |
| NSIDC | National Snow and Ice Data Center |
| NSOF | NOAA Satellite Operations Facility |
| NSOM | Network and Space Operations and Maintenance |
| NSPAR | Nonstandard Parts Approval Request |
| NSS | Navigation Satellite System |
| NSS NextGen | Navigation Satellite System Next Generation Navigation Subsystem |
| NSSK | North/South Station-keeping |
| NSSL | National Severe Storm Laboratory |
| NSSTC | National Space Science and Technology Center |
| NSTISSP | National Security Telecommunications and Information Systems Security Policy |
| nT | nano Tesla |
| NTE | Not to Exceed |
| NTGSE | WindowsNT Ground Support Equipment |
| NTIA | National Telecommunications and Information Administration |
| NTP | Network Time Protocol |
| NTSB | National Transportation Safety Board |
| NVD | National Vulnerability Database |
| NVM | Non-Volatile Memory |
| NVR | Non-Volatile Residue |
| NWA | National Weather Association |
| NWCs | National Weather Centers |
| NWP | Numerical Weather Prediction |
| NWS | |
| NWSTC | NWS Training Center |
| NWSTG | NWS Telecommunications Gateway |