Mainsail

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

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Related M-terms

Mooring

A permanent ground tackle — anchor, chain, and buoy — to which a vessel can secure instead…

Mainsheet

The control line that trims the mainsail in and out, running through a block system on the…

Marlinspike

A tapered metal spike used to loosen knots, open rope lays, and work splices.

MMSI

Maritime Mobile Service Identity — a unique nine-digit number issued to each DSC-VHF/HF ra…

Mast

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

Masthead

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

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