| Abbreviation | Definition |
|---|---|
| NASDA | National Space Development Agency (of Japan) |
| NASP | National Aerospace Plane |
| NASTRAN | NASA Structural Analysis |
| NATF | Naval Air Test Facility |
| NATL | National |
| NAVAID | Navigation Aid |
| NAVDAD | Navigationally Derived Air Data |
| NAVEX | Navigation Experiments (Spacelab D-1 Experiment) |
| NAVPOOL | Navigation Parameter Common Pool |
| NAVSAT | NAVigation SATellite |
| NAVSTAR | NAVigational STAR |
| NB | Navigation Base |
| NB | Neutral Buoyancy |
| Nb | Niobium |
| NB | Nitrogen Base |
| NB | No-Bias |
| NBF | Neutral Buoyancy Facility |
| NBL | Neutral Buoyancy Laboratory |
| NBS | Neutral Buoyancy Simulator |
| NBSP | Non Breaking Space People |