Mole
Nautical Almanac
Mizzen (mizen)
Mizzen (mizen)
Mitre
Mitre
Miss stays, to
Miss stays, to
Millibar
Millibar
Middle ground
Middle ground
Microspheres
Microspheres
MHWS
MHWS
MHWN
MHWN
Metacentre
Metacentre
Meridian
Meridian
Mercator’s projection
Mercator's projection
Measured distance
Measured distance
Marina
Marina
Mayday
Mayday
Masthead light
Masthead light
Masthead float
Masthead float
Master
Master
Mast coat
Mast coat
Mast
Mast