At Sea Glossary - M
main mast
The tallest (possibly only) mast on a boat.
mainsail
The main sail that is suspended from the main mast.
main sheet
The line used to control the mainsail.
main topsail
A topsail on the main mast.
make fast
To attach a line to something so that it will not move.
marina
A place where boats can find fuel, water and other services. Marinas also contain slips where boats can stay for a period of time.
mast
Any vertical pole on the boat that sails are attached to. If a boat has more than one mast, they can be identified by name.
master
The person in charge of a vessel. The captain.
masthead
The top of a mast.
mate
An assistant to the captain.
mayday
An internationally recognized distress signal used on a radio to indicate a life-threatening situation. Mayday calls have priority over any other radio transmission and should be used only if there is an immediate threat to life or vessel. More urgent than a pan pan orsecurite call.
meridian
A longitude line. Meridians are imaginary circles that run through both poles.
mizzen mast
A smaller aft mast on a ketch or yawl rigged boat.
mizzen sail
The sail on the aft mast of a ketch or yawl rigged sailboat.
mizzen staysail
A small sail that is sometimes placed forward of the mizzen mast.
monohull
A boat that has only one hull, as opposed to multihull boats such as catamarans or trimarans.
moor
To attach a boat to a mooring, dock, post, anchor, etc.
mooring
A place where a boat can be moored. Usually, a buoy marks the location of a firmly set anchor.
mooring buoy
A buoy marking the location of a mooring. Usually attached to ananchor by a small pendant.
mooring line
A line used to secure a boat to an anchor, dock or mooring.
Morse code
A code that uses dots and dashes to communicate by radio or signal lights.
motor
1) An engine.
2) The act of using an engine to move a boat.
motor sailer
A boat designed to use its motor for significant amounts of time and use the sails less often than a normal sailboat.
mount
1) An attachment point for another object.
2) The act of putting an object on its mount.
multihull
Any boat with more than one hull, such as a catamaran ortrimaran.
mushroom anchor
A type of anchor with a heavy, inverted mushroom-shaped head. Mushroom anchors are used to anchor in mud and other soft ground.
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