A pin placed through the head of a rudder to prevent it from being lost.

One of the 4 cardinal compass points. North is the direction toward the North Pole and is at 0

The top point of the line about which the earth rotates.

Polaris, the North Star, is visible in the northern hemisphere and indicates the direction of north. In the southern hemisphere the Southern Cross is used to find the direction of south.

Wind coming from the north.

Front of a container or trailer - opposite the tail.

Said of a vessel when unable to maneuver.

Same as not under command.

Periodic publications containing details of any alterations to charts, to keep them up to date.

A projecting aperture at the end of a tube, pipe etc. serving as an outlet for compressed air. Reduces the demand on the compressor by generating the highest thrust and volume for the lowest possible air consumption.

The stationary seating surface, the inlet of a valve.

ACRONYM - National Pipe Thread standard. A description of a specific pipe thread

ACRONYM - National Pipe Thread tapered. A description of a specific pipe thread

A kind of navigational buoy

Isolated rocky peak rising from a sheet of inland ice.

[meaning]

A measurement. Outside diameter.

Overseas Private Investment Corporation.

A material made of tarred hemp or manila rope fibers, used for caulking seams of decks and sides of a wooden ship in order to make them watertight.