| Acronym | Definition |
|---|
| NISS | NSG (Nuclear Suppliers Group) Information Sharing System |
| NISS | National Intelligence and Security Service (Sudan) |
| NISS | National Institute of Statistical Sciences |
| NISS | National Institute for Strategic Studies (various locations) |
| NISS | National Information Services and Systems (UK) |
| NISS | New ICMI Study Series (International Commission on Mathematical Instruction) |
| NISS | National Independent Statistical Service |
| NISS | Numéro d'Identification Sécurité Sociale (Belgian Social Security Identification Number) |
| NISS | National ITV Satellite Schedule |
| NISS | Network and Information Security Services |
| NISS | National Industrial Security System (Department of Defense) |
| NISS | National Institute of Space Sciences |
| NISS | Nuclear Information Suppliers System |
| NISS | Node-Inclusive Span Survivability |
| NISS | Nonimmigrant Information System |