Maritime Terms, Abbreviations and Acronyms

Maritime abbreviations and acronyms go back to those days we used telegram and telex to communicate. The business model for telex and telegrams was “pay per letter”. Even though the telegrams and telexes have been retired, we still use the maritime abbreviations daily.

Below you will find a comprehensive list of terms, abbreviations, and acronyms used in the maritime industry, sorted in alphabetical order. You can search for an acronym or write a word and find the abbreviations where the word is included.

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Malaccamax

Malaccamax is a naval architecture term for the largest size of ship capable of fitting through the 25 metres (82 ft)-deep Strait of Malacca.

Malpractice

A carrier giving a customer illegal preference to attract cargo. This can take the form of a money refund (rebate); using lower figures than actual for the assessment of freight charges (undercubing); misdeclaration of the commodity shipped to allow the assessment of a lower tariff rate; waiving pub- lished tariff charges for demurrage, CFS handling or equalization; providing specialized equipment to a shipper to the detriment of other shippers, etc.

Mandamu

A writ issued by a court; requires that specific things be done.

Manifest

a detailed summary sheet of all cargo being carried for each vessel trip; information also includes origin, destination, value, number, etc.

Manifold

Area of a tanker featuring pipes and valves for intake and offloading of cargo.

MAP

Mono-ammonium phosphate

Margarines

Margarines are semi-solid or consistent fatty foods originally developed to imitate dairy butter. They therefore contain a proportion of emulsified aqueous phase similar to that found in butter. The amount of moisture permitted in margarine is limited by law to a maximum of 16% in most countries while the fat content is required to be at least 80%. The aqueous phase may contain dissolved salt and an amount of milk solids treated to impart a butter-like flavour. Permitted colour is often added to give a butter-like pale yellow. Vitamins A and D are also often added. While the original purpose in developing margarine over 100 years ago was to supplement inadequate supplies of butter, there has been considerable diversifications of margarine products, particularly in the last 30 years. The following main types can be listed - a. table margarines in packets; b. table margarines in tubs; c. tub margarine with a high content of poly-unsaturated oils; d. domestic cooking margarines; e. industrial margarines for general purposes, and f. industrial margarines for puff pastry. Nowadays, the trend is to reduce the fat content to produce spreads or ""halvarines"".

Marine Insurance

Broadly, insurance covering loss or damage of goods at sea. Marine insurance typically compensates the owner of merchandise for losses sustained from fire, shipwreck, etc., but excludes losses that can be recovered from the carrier.

Marine Oils

The first common source of marine oil was obtained from whales. Today, whale numbers have been reduced to insignificance. Various types of fish are caught for processing into meal and oil, for example, herring, menhaden and anchovy. After refining and partial hydrogenation fish oils, are useful ingredients for margarines and shortenings. World production is close to one million tonnes.

Marine pollutant

Substances, articles or materials which, if released into the aquatic environment, may cause serious environmental damage.

Maritime

Business pertaining to commerce or navigation transacted upon the sea or in seaports in such matters as the court of admiralty has jurisdiction.

Maritime Domain

It is all areas and things of, on, under, relating to, adjacent to, or bordering on a sea, ocean, or other navigable waterway, including all maritime related activities, infrastructure, people, cargo, and vessels and other conveyances.

Maritime Domain Awareness (MDA)

It is the effective understanding of anything associated with the global maritime domain that could impact the security, safety, economy, or environment of the United States.

Maritime lien

A right in the propery of a ship, conferred by law for seamens wages, salvage, etc.

Maritime Security and Safety Information System (MSSIS)

It shares and displays vessel Automated Identification System (AIS) data real–time with multiple international users through a web–based, password–protected system.

Maritime Waterways

Inland waterways linked to the sea, basically used for the traffic of seagoing vessels and designated as such under national law

Mark I

WW designation for ro-ro carriers built in 1978-79

Mark II

WW designation for ro-ro carriers built in 1984

Mark III

WW designation for ro-ro carriers built in 1996

Mark IV

WW designation for ro-ro carriers built in 2000-01

Market related

see FLOATING PRICE

Markets

Markets for oleochemicals continue to evolve, with niche markets developing continually. Nonetheless, the main end-use markets include building auxiliaries, candles, cleaning agents, cosmetics, detergents, fire extinguishing agents, flotation agents, food emulsifiers, insecticides, pharmaceuticals, plastics, rubber, soaps and detergents, textiles and tyres.

Marking

Letters, numbers, and other symbols placed on cargo packages to facilitate identification. Also known as marks.

Marlinespike

A pointed metal spike, used to separate strands of rope in splicing.

MARPOL

The abbreviated term for the International Convention for the Prevention of Pollution by Ships (MARine POLlution) The International regulations concerning the construction of vessels and procedures to be followed to prevent pollution of the sea by oil, no

MARPOL 73/78

International Convention for the Prevention of Pollution from Ships, 1973, as modified by the Protocol of 1978 relating to the International Convention for the Prevention of Pollution from Ships, 1978

Marpol Category

The Pollution Category (X, Y, Z) assigned to each product under Annex II of MARPOL 73/78. OS means the product was evaluated, and found to fall outside the categories X, Y, or Z. I indicates that the product is an Annex 1 product.

MARPOL Pollution Category

This refers to the pollution categories designated in the “MARPOL 73/78” regulations: X to Z - Pollution category of the cargo as evaluated by MARPOL. “X” means highest environment impact OS - Pollution category is evaluated, but outside categories X to Z. Annex I - Included in 'List of Oils'

MARS

Nautical Institute Marine Accident Reporting System

MarView

It is an integrated, data–driven environment providing essential information to support the strategic requirements of the United States Marine Transportation System and its contribution to economic viability of the nation.

Mass explosion

Explosion which affects almost the entire load virtually instantaneously.

Master

An officer qualified to command a ship. Usually refers to the Captain.

Master Inbound

U.S. Customs’ automated program under AMS. It allows for electronic reporting of inbound (foreign) cargoes in the U.S.

Mate’s Receipt

An archaic practice. An acknowledgement of cargo receipt signed by a mate of the vessel. The possessor of the mate’s receipt is entitled to the bill of lading, in exchange for that receipt.

MATS

Material(s)

MAX

Maximum

MAXBACTAP

Max But As Close To As Possible

MB

Merchant Broker

MB/T

Motor blocks/ turnings

MBL

Minimum Breaking Load

MBM

Multi-Buoy Moorings

MBM

1,000 board feet. One MBM equals 2,265 C.M.

MBTE

Methyl tert-butyl ether

MCFS

Master Container Freight Station. See CFS.

MCO

Maximum continous output

MCR

Maximum Continuous Rating - Maximum warranted power an engine can sustain under continuous operation.

MCT

Medium-Chain Triglyceride. Triglycerides containing fatty acid chains of 6-10 carbon atoms which are readily absorbed by the body.

MDO

Marine diesel oil

MDSE

Merchandise

MDWT

Metric DeadWeight Tons

ME

Main Engine

MEA

Monoethanolamine

Measurement Cargo

Freight on which transportation charges are calculated on the basis of volume measurement.

Measurement Ton

40 cubic feet.

MECH

Mechanical

Mechanical Lift Dock

A lifting dock facility using winches to lower and raise platform

Mechanically Ventilated Container

A container fitted with a means of forced air ventilation.

Mechanism of toxicity

The way in which a chemical alters basic biological functions and structures in order to exert its toxic effect(s)

MED

Mediterranean

Medium-speed diesel

Moderately large diesel engines such as those which propel large boats and heavy-duty locomotives. These engines burn a heavy gasoil which sometimes takes their name.

MEG

Middle East Gulf

Megaports Initiative

It is a National Nuclear Security Administration (NNSA) initiative, started in 2003. It teams up with other countries to enhance their ability to screen cargo at major international seaports. The Initiative provides radiation detection equipment and trains their personnel to specifically check for nuclear or other radioactive materials. In return, NNSA requires that data be shared on detections and seizures of nuclear or radiological material that resulted from the use of the equipment provided.

MEK

Methyl Ethyl Ketone

Melting

When heated sufficiently, a solid changes state to a liquid. The melting of a fat depends on its previous triglyceride composition. The baking or spreading performance of commercial fats depends greatly on their melting behaviour. Solid fat content measurement is commonly used to monitor this behaviour.

MEM

Moment

MEMO

Memorandum

Memorandum Bill of Lading

An in–house bill of lading. A duplicate copy.

Memorandum Freight Bill

See Multiple Container load Shipment.

MeOH

Methyl Alcohol = Methanol

MEPC

Marine Environment Protection Committee

Mercaptans

Mercaptan sulfur. Excessive concentrations of these malodorous organic sulfur molecules make motor gasoline unmerchantable. Blenders, therefore, want to know the mercaptan content of components they could consider buying. The kerosene trade pays careful attention to this form of sulfur too. Jet fuel, and sometimes burning kerosene, have mercaptans limits.

merger

The joining of two or more (shipowning) companies

MESA

Most Environmentally Sensitive Area

MESSRS

Messieurs or Gentlemen or Sirs

Metacenter or transverse metacenter

Ship Stability: The highest point to which G may rise and still permit the vessel to have positive stability. Found at the intersection of the line of action of B when the ship is erect with the line of action of B when the ship is given a small inclination.

Metals content

A specification of concern to buyers of fuel oil and vacuum gasoil.Heavy metals, such as nickel, vanadium, and copper, poison cat-cracking catalysts.Most refiners specify a maximum metals limit for the catfeed and vacuum unit feedstock they would consider purchasing.Traces of metal, particularly lead, also worry reformer feedstock buyers.

Metaxylene

Metaxylene is an isomer of mixed xylene. It is used as an intermediate in the manufacture of polyesters for coatings, inks, reinforced plastics, and packaging applications.

Meter

39.37 inches (approximately).

Methaemoglobin generator

A substance capable of converting the oxygen carrying molecule (haemoglobin) in the red blood cell to an oxidized form (methaemoglobin), which has a reduced capacity to transport oxygen.

Methane

A colorless, odorless, flammable gas that occurs abundantly in nature as the chief constituent of natural gas, as a component of firedamp in coal mines, and as a product of the decomposition of organic matter. Methane is used as a fuel and as a starting material in chemical synthesis.

Methanol

Methanol, a colorless alcohol, is a chemical used in the production of formaldehyde, acetic acid and methyl methacrylate (MMA), and is used as a solvent in many applications. It is also used to produce MTBE.

Methyl Esters

The fatty acid composition of an oil is normally determined by using Gas Liquid Chromatography of the fatty acid methyl esters (FAME analysis). The methyl ester derivatives of fatty acids are comparatively volatile. Methyl esters of fatty acids are conveniently prepared by displacing the glycerol from the triglycerides of the oil, using methanol in the presence of an alkaline or acidic catalyst.

Methylamines

Methylamines (mono-, di- and tri) and their derivatives are alkaline substances that are produced by reacting ammonia and methanol, in the gas phase at high temperatures and high pressure. Methylamines are available as anhydrous liquefied gases and as aqueous solutions.

Metric Ton

2,204.6 pounds or 1,000 kilograms.

MEX

Mexico

MF

Medium Frequency

MFAG

Medical First Aid Guide

MFG

Manufacturing

MFRS

Manufactures

MG/R

Managing/Manager

MGA

Master''s general account

MGO

Marine gas oil

MGT

Management

MH

Main hatch

MHE

Materials handling equipment

MHHW

Mean Higher High Water

MHI

Car carriers built at Mitsubishi Heavy Industries in 2004-06

MHW

Mean High Water

MHWN

Mean high water neaps: and

MHWS

Mean High Water Spring Tides
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