MOB button

A dedicated button on a GPS, chartplotter, or autopilot that marks the current position the instant a person goes overboard, giving an immediate waypoint to navigate back to.

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Related M-terms

Mainmast

The taller (main) mast on a vessel with more than one mast.

Masthead

The top end of the mast, often carrying a wind instrument, anchor light, VHF antenna, and …

Maststep

The fitting (on deck or on the keel) into which the foot of the mast is stepped.

Mainsail

The principal sail set on the (main) mast of a sloop, cutter, ketch, or yawl.

MFD

Multi-Function Display — a large chartplotter screen able to show radar, AIS, sonar, engin…

Mast

The vertical spar — originally timber, today commonly aluminium or carbon — from which the…

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