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.

If you think some abbreviations are missing, send us an e-mail at post@maritimeoptima.com or open the chat icon on the bottom of this page.

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MIAP

Mortgagee interest additional perils pollution

MIBK

Methyl Isobutyl Ketone

MIC

Man-In-Charge

Micro-Bridge

Interior point intermodal service similar to mini-bridge, except that cargo originates or terminates at an inland city rather than another port city. The cargo moves on a single (ocean) bill of lading to and from the interior point and the port.

Microbridge

A cargo movement in which the water carrier provides a through service between an inland point and the port of load/discharge. The carrier is responsible for cargo and costs from origin on to destina- tion. Also known as IPI or Through Service.

MICS

Member of The Institute of Chartered Shipbrokers, London

MID

Middle

Mid-point

The temperature where 50 percent (weight or volume basis, as specified) of a natural material or refined product has boiled.Sometimes called 50 percent point.

Middle distillates

Products heavier than motor gasolinenaphtha and lighter than residual fuel oil.This range includes heating oil, diesel, kerosene, and jet kero.

Midship

Approximately in the location equally distant from the bow and stern

MII

Mortgagee interest insurance

Mile

A unit equal to 5,280 feet on land.A nautical mile is 6076.115.

Mill Scale

A thick oxide coating formed on the steel when heated, e.g., in connection with hot working or heat treatment

MIN

Minute or Minimum

MIN/MAX

Minimum/Maximum (cargo quantity)

MIN/MAX OR

Minimum / maximum

Minehunter

A naval vessel equipped for detecting explosive marine mines

Minelayer

A naval vessel designed for laying marine mines

Minesweeper

A naval vessel equipped for detecting, destroying, removing, or neutralizing explosive marine mines

Mini Landbridge

An intermodal system for transporting containers by ocean and then by rail or motor to a port previously served as an all–water move (e.g., Hong Kong to New York over Seattle).

Mini-Bridge

Substitution of rail or truck service for water transportation between two U.S. port cities for cargo originating or terminating in a port city.

Minimum Bill of Lading

A clause in a bill of lading which specifies the least charge that the carrier will make for issuing a lading. The charge may be a definite sum or the current charge per ton for any specified quantity.

Minimum Charge

The lowest charge that can be assessed to transport a shipment.

Mining Vessel

A vessel equipped for offshore mining operations, most commonly diamonds

MIO

Millon(s)

MIP

Marine insurance policy

MISC

Miscellaneous

Miscible

In this guidebook, means material that mixes readily with water.

Mission Ship

A mobile vessel used for missionary work

MITI

Ministry of International Trade & Industry (JP)

Mixed Container Load

A container load of different articles in a single consignment.

MKT

Market

ML

Motor launch

MLB

Mini-landbridge

MLC

Meters of Liquid Column

MLD

Moulded

MLLW

Mean low low water

MLS

Miles

MLW

Mean low water

MLWN

Mean low water neaps. Average depths of water available at the times of low and of high tides during periods of Neap Tides

MLWS

Mean Low Water Spring Tides

MM

Marketing Manual

MM

Engine Room (OCIMF acronym)

mm

millimetre

MMA

Methyl Methacrylate. A chemical derived from propylene, used for the manufacture of polymethyl methacrylate and also for polymer dispersions and other resins.

MMFB

Middlewest Motor Freight Bureau.

MMPD

Maximum Most Probable Discharge

MMS

APPE Monthly Monitoring of Monomers. APPE is a major group within the Association of Petrochemicals Producers in Europe (APPE). For more information, click here.

MMSI

Maritime Mobile Selective Call Identity Code

MNLO

Merchant Navy Liaison Officer

MO

Managing Owner

MOA

Memorandum of Agreement: A contract form specifying the terms and conditions covering the sale and purchase of a merchant ship

MOD

Ministry of Defence

Modified Atmosphere

A blend of gases tailored to replace the normal atmosphere within a container.

MODU

Mobile Offshore Drilling Units

Mogas

An abbreviation of motor gasoline.

MOH

Medical Officer of Health

Moisture

Since water is only very slightly soluble in fats, it is present only in small amounts and is referred to as moisture. Moisture in oils and fats may be determined by drying, distillation, absorption or titrimetry. The presence of water, especially when in large amounts, may enhance hydrolysis especially at elevated temperatures.

MOL

More or Less

Molasses Tanker

A tanker for the bulk carriage of molasses

MOLCHOP

More Or Less CHarterers OPtion

MOLCHOPT

More or less in Charterers option

MOLCHOPT or MOLCO

More or Less Charterers Option

MOLCO

More or less Charterers option

Molecule

Chemical combination of two or more atoms of the same chemical element (such as O2 - which is Oxygen) or different chemical elements (such as H2O - which is water).

MOLOO

More or less in owners' option

Molten Sulphur Tanker

A tanker for the bulk carriage of molten sulphur in insulated tanks at a high temperature

MOM

Moment

Moment

Ship Stability: The product of two numbers, for example the force or weight moved multiplied by a distance

MON

MONitors (fire)

MON (Motor Octane Number)

A rating of the anti-knock properties of a finished motor gasoline or blendstock. The test determines MON simulates demanding engine operating conditions such as substantial loads and high speeds. The MON method yields lower numbers than the RON (research octane number) test which reflects milder conditions.

Monoglyceride (Monoacylglycerol)

Monoglyceride is a compound used as an emulsifier in margarine/peanut butter etc, to help the uniform dispersion of oil in water. Monoglycerides do not occur naturally in appreciable quantities except in fats and oils that have undergone partial hydrolysis. For instance, fats and oils that are damaged or spoiled in the field or in storage and have abnormally high free fatty acid contents will have corresponding high di- or monoglyceride content.

Monomer

A molecule that can combine with others to form a polymer.

Monomer

One molecular unit which links with others of its own or a similar kind to form a Styrene monomers, for instance, connect to form the familiar plastic, polystyrene.

Monounsaturated

A fatty acid containing only one pair of carbon-carbon double bonds.

Montreal Protocol

International agreement which aims to protect the ozone layer. Forms part of the UN Environmental Programme (UNEP)

Mooring

An arrangement for securing a ship to a mooring buoy or pier

Mooring Buoy

A mooring buoy

Mooring Vessel

A vessel equipped to assist with the mooring and/or anchoring of larger vessels. Typically it will have a frame to prevent the ropes and chains fouling on the superstructure

Mooring Vessel, Naval Auxiliary

A naval auxiliary vessel designed to assist with the mooring and or anchoring of larger vessels

MOP

Muriate of Potash

MOS

Months

MOS or MTHS

Months

MOT

Ministry of Transport or Monthly Overtime

Motor alkylate

Full name of a gasoline blendstock often simply called alkylate.

Motor gasoline

Petroleum-derived fuel blend intended to power spark-ignited internal combustion automobile engines. This propellant's boiling range can span C4 through 430 F. In practice, it usually has a somewhat lower end point. Mogas must meet various specifications depending on the where and when it sells. Governments, climates, seasons, and market organizations all impose quality restrictions on the product. Most grades intended for modern motors resemble the fuel described by ASTM D 439. Mogas differs in some respects from aviation gasoline (avgas) a mixture blended for internal combustion aeroplane engines

MOU

Memorandum of Understanding

MOU PARIS

Memorandum of Understanding (Paris)

MP

Propylene Glycol Methyl Ether

MPA

Propylene Glycol Methyl Ether Acetate

MPG

Monopropylene Glycol. Produced by reacting propylene oxide with water. Monopropylene glycol is widely used for its solvent properties in the pharmaceutical, food, flavor and personal care industries. It is more widely used as an anti-freeze/de-icer, grinding aid, heat transfer fluid, component in hydraulic fluids, humectant, and surface coating industries.

MPG / USP

Pharmaceutical grade monopropylene glycol

MPH

Miles per hour

MPP

Multi-purpose (type of ship)

MR

Medium Range (tanker): A vessel designed for carrying refined petroleum products in bulk tanks (25,000 dwt - 44,999 dwt approx). MR tankers primarily transport refined oil products on intra-regional routes between the oil refineries. Only on rare occasions are they employed over longer distances.

MRA

Marine Response Alliance

MRNG

Morning

MRV

Monitoring Reporting and Verification

MRX

Medium range cross-purpose tanker

MS

Months after sight or Machinery survey
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