MANIFEST - Inventory of cargo onboard the vessel
MAX - Maximum
MB - Merchant Broker
MBT - Motorblock turnings
MARAD - Maritime Administration (branch of U.S. Dept. of Transportation concerned with shipping)
MARPOL - The International Convention for Prevention of Pollution from ships 1973 as modified by the Protocol of 1978
MBT - Motor blocks & turnings (types of scrap)
MDO - Marine diesel oil
MED - Mediterranean (sea)
MECH - Mechanical
MESSRS Messieurs or Gentlemen or Sirs
MEMO - Memorandum
MIDSHIP - Approximately in the location equally distant from the bow and stern
MIC - Man in charge
MIN - Minute or minimum
MLD - Moulded
MOL - More or less
MOM - Moment
MOS - Months
MPP - Multi purpose
MIN/MAX - Minimum/maximum (Cargo quantity)
MOA - Memorandum of Agreement (Contract form used for the purchase and sale of ships)
MOLOO - More or less, quantity in owners option
MOORING - Securing a ship to a mooring buoy or a pier
MOLCHOPT - More or less quantity in Charterers option
MR - Mate's receipt
MST - Measurement
MT - Metric ton (1000 kilograms)
MV - Motor Vessel