| Abbreviation | Definition |
|---|---|
| NIBI | Dutch Institut for Biology |
| NIBI | Nederlands Instituut voor Biologie |
| NICCS | Newell Integrated Child Care Society |
| NIF | Norske Sivilingeniørs Forening |
| NIF | Norske Sivilingenirs Forening |
| NIF | Norwegian Society of Chartered Engineers |
| NIOS | Northern Ireland Optometric Society |
| NIP | Dutch Institute of Psychologists |
| NIP | Nederlands Instituut van Psychologen |
| NIRIA | Nederlandse Ingenieursvereniging |
| NIRIA | Netherlands Association of Engineers |
| NIRPS | Northwest Indiana Railroad Preservation Society |
| NJAS | New Jersey Academy of Science |
| NJBS | New Jersey Bluebird Society |
| NJHS | National Junior Honor Society |
| NJHS | New Jersey Historical Society |
| NJMS | New Jersey Miniatures Society |
| NJPS | New Jewish Publication Society |
| NJSZT | John v. Neumann Computer Society |
| NJSZT | Neumann János Számítógép-tudományi Társaság |