| NAFTA | North American Free Trade Agreement |
| NAICC | Navigation-Aided Intelligent Cruise Control |
| NCAP | New Car Assessment Programme |
| NDH | Navigation Display Head |
| NDOCP | Non-Dispersant Olefin CoPolymer |
| NG | Natural Gas |
| NGEO | Natural Gas Engine Oil |
| NGV | Natural Gas Vehicle |
| NGVA | Natural Gas Vehicle Association |
| NHTSA | National Highway Traffic Safety Administration |
| NiMH | Nickel Metal Hydride |
| NIST | National Institute of Standards and Technology (US) |
| NLEV | National Low-Emission Vehicle |
| NLGI | National Lubricating Grease Institute (US) |
| NM | Newtonmetre Measurment of torque |
| NMHC | Non-Methane Hydrocarbons |
| NMMA | National Marine Manufacturers Association |
| NMOG | Non-Methane Organic Gases |
| NOACK | Apparatus/Method for Volatility Measurement |
| NOx | Nitrogen Oxides |
| NPRA | National Petrochemical & Refiners Association (US) |
| NSF | National Sanitation Foundation |
| NV | Night Vision |
| NVFEL | National Vehicle and Fuel Emissions Laboratory (US-EPA) |
| NVFL | National Vehicle and Fuel Lab (EPA) |
