- magnetic azimuth
- magnetic compensator
- magnetic needle
- magnetic storm
- magnetic telegraph
- magnitude of an eclipse
- magnitudes of stars
- mahone
- mahonna
- maon
- maid
- maiden
- mail
- mail-shell
- main
- main-body
- main-boom
- main-brace
- main-breadth
- main-capstan
- main-course
- main-guard
- main-hold
- main-ice
- main-jeers
- main-keel
- main-piece
- main-piece of the rudder
- main-post
- main royal-mast
- main-sail
- main-sail haul!
- main-shaft
- mainsheet-horse
- main-spring
- main-staysail
- main-tack block
- main-tackle
- main-tackle pendant
- main-top bowline
- main-topsail haul!
- main-transom
- main-wales
- main-yard men
- maister
- maize
- major
- major axis
- major-general
- major of brigade
- make, to
- make a good board
- make a lane there!
- make bad weather, to
- make fast
- make free with the land, to
- make head-way
- make it so
- make lee-way, to
- make ready!
- makes
- make sail, to
- make stern-way, to
- make the land, to
- make water, to
- making iron
- making off
- mala fides
- malduck
- malkin
- malingerer
- mallard
- mollymauk
- mallemak
- mallemaroking
- mallet
- mallow
- maltha
- man
- man, to
- man, isle of, battery
- manacle
- manarvel, to
- manatee
- manati
- man-bound
- man-broker
- manby's mortar
- manche of mangalore
- manchineel
- mandarin
- mandilion
- mandril
- manger
- mangonel
- mangonize, to
- man-handle, to
- man-hole
- man-hunting
- manifest