| Abbreviation | Definition |
|---|---|
| NIS | Network Imaging Solutions, Inc. |
| NIS | Network Integration Services |
| NIS | Network Integrity Systems |
| NIS | Network Interpreting Service, Inc. |
| NIS | Norwegian International Shipping |
| NISC | National Information Services Corporation |
| NISCO | Nanjing Iron & Steel Co., Ltd. |
| NISCO | Nelson Industrial Steam Company |
| NISCO | Nishikawa Cooper, LLC |
| NISI | Northwest Instrument Systems, Incorporated |
| NISOC | National Iranian South Oilfields Company |
| NISSAN | Nihon Sangyo (which basically means "Japan Industry.") |
| NIT | New Infrared Technologies |
| NITC | National Iranian Tanker Company |
| NITEL | Nigerian Telecommunications Limited |
| NITI | Net Integration Technologies Inc |
| NITL | National Investment Trust, Limited |
| NJA&A | New Jersey Art and Antiques |
| NJAWBO | New Jersey Association of Women Business Owners |
| NJBE | New Jersey Business Exchange |