| Abbreviation | Definition |
|---|---|
| NIEWS | NTCS-A (Navy Tactical Command System - Afloat) Imagery Exploitation Work Station |
| NIEWS | NTCS-A Imagery Exploitation Work Station |
| NIEX | No-Notice Interoperability Exercise |
| NIEXPG | No-Notice Interoperability Exercise Planning Group |
| NIF | Naval Industrial Fund |
| NIF | Nonindustrial Facilities |
| NIFFT | Non-cooperative Identification Friend or Foe Technology |
| NIFFTE | Non-Cooperative Identification Friend or Foe Technology |
| NIFT | Navigator Introductory Flight Training |
| NII | National Information Infrastructure |
| NIIB | National Geospatial Intelligence Agency Imagery Intelligence Brief |
| NIL | National Information Library |
| NIMA | National Imagery and Mapping Agency |
| NIMBY | Not In My Blue Yonder |
| NIMCAMP | National Information Management and Communications Master Plan |
| NiMH | Nickel-Metal Hydride |
| NIMSR | Non-consumable Item Material Support Request |
| NIO | New Initiatives Office |
| NIOC | Navy Information Operations Command |
| NIP | National Intelligence Program |