Nun

In the IALA Region B system, a red even-numbered conical buoy marking the starboard side of a channel when entering from seaward, usually paired with green cans on the opposite side.

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Related N-terms

Navigation rules

The body of law — internationally the COLREGs — designed to prevent collisions at sea.

NMEA 2000

A modern CAN-bus data network for marine electronics, allowing plug-and-play interconnecti…

NMEA 0183

A legacy serial data standard defined by the US National Marine Electronics Association, u…

No-go zone

The sector of directions into the wind — roughly ±45° — where a sailing vessel cannot make…

Nautical mile

The standard unit of distance at sea, 1852 m or 6076 ft, originally defined as one minute …

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