(nautical) The process of swinging and compensating a ship or aircraft compass by determining and reducing the deviation coefficients and recording the residual deviations; now done by computer.

Any of the horizontal directions indicated on a compass. There may be 4, 8, 16, 32, 64, or even 128 compass points on a compass, depending on its size and accuracy.

A gyrocompass.

(military, nautical) An instrument containing a freely suspended magnetic element which displays the direction of the horizontal component of the Earth’s magnetic field at the point of observation.

(geometry, geomagnetism) The combination of variation and deviation which is the horizontal angle between the direction indicated by a magnetic compass and true north.

(navigation) A graduated circle, usually marked in degrees, indicating directions and printed or inscribed on an appropriate medium.

(nautical) A compass installed in the cabin so that the captain or other officer may check the course of a ship without going to the deck; often upturned and suspended from the ceiling.

An arcograph. / A small pair of compasses, one leg of which carries a pencil or pen for drawing circles. Its legs are often connected by a bow-shaped spring rather than a joint.

plural of bow compass

plural of beam compass