To efficiently wind the pole shoes lying close together of electronically commutated multipole three-phase motors, they will be coated with insulation and directly wound with the needle winding method.

Near-isothermal compression (and expansion) is a process in which a gas is compressed in very close proximity to a large incompressible thermal mass such as a heat absorbing and releasing structure (HARS) or a water spray.

Natural-gas condensate, also called natural gas liquids, is a low-density mixture of hydrocarbon liquids that are present as gaseous components in the raw natural gas produced from many natural gas fields.

Natural uranium refers to uranium with the same isotopic ratio as found in nature. It contains 0.711% uranium-235, 99.284% uranium-238, and a trace of uranium-234 by weight (0.0055%).

Natural resources are resources that exist without any actions of humankind.

Natural refrigerants are substances that serve as refrigerants in refrigeration systems.

A fossil natural nuclear fission reactor is a uranium deposit where self-sustaining nuclear chain reactions have occurred.

A monopoly in an industry in which high infrastructural costs and other barriers to entry relative to the size of the market give the largest supplier in an industry, often the first supplier in a market, an overwhelming advantage over potential competitors.

A natural gas vehicle (NGV) is also an alternative fuel vehicle that uses compressed natural gas (CNG) or liquefied natural gas (LNG).

Natural gas is a commodity that can be stored for an indefinite period of time in natural gas storage facilities for later consumption.

Natural gas (also called fossil gas; sometimes just gas) is a naturally occurring hydrocarbon gas mixture consisting primarily of methane, but commonly including varying amounts of other higher alkanes, and sometimes a small percentage of carbon dioxide, nitrogen, hydrogen sulfide, or helium.

A cooling tower design that uses natural convection currents of hot air to draw air into the tower to cool the water.

Natural convection is a type of flow, of motion of a liquid such as water or a gas such as air, in which the fluid motion is not generated by any external source (like a pump, fan, suction device, etc.) but by some parts of the fluid being heavier than other parts.

Natural climate forcings include changes in the Sun's brightness and volcanic eruptions that inject light-reflecting particles as high as the stratosphere.

The National Institute for Occupational Safety and Health (NIOSH) is the United States federal agency responsible for conducting research and making recommendations for the prevention of work-related injury and illness.

The National Ignition Facility (NIF), is a large laser-based inertial confinement fusion (ICF) research device, located at the Lawrence Livermore National Laboratory in Livermore, California.

Nanotechnology, also shortened to nanotech, is the use of matter on an atomic, molecular, and supramolecular scale for industrial purposes.

The nanometre is a unit of length in the metric system, equal to one billionth (short scale) of a metre (0.000000001 m).

Nanocrystal solar cells are solar cells based on a substrate with a coating of nanocrystals.

The body of a propeller-type wind turbine, containing the gearbox, generator, blade hub, and other parts.