List of acronyms: M

(Main list of acronyms)


 * m – (s) Metre – Milli
 * M – (s) Mega- – One thousand (in Roman numerals)

MA

 * mA – (s) Milliampere
 * Ma – (s) Megaannum
 * MA
 * (s) Madagascar (FIPS 10-4 country code)
 * (i) Marijuana Anonymous
 * (i) Master of Arts
 * Massachusetts (postal symbol)
 * Megaampere
 * Morocco (ISO 3166 digram)
 * MAA – (i) Mathematical Association of America
 * MAAC – (a) Metro Atlantic Athletic Conference
 * MAC
 * (s) Macau (ISO 3166 trigram)
 * (a) U.S. Military Airlift Command (1966–1992)
 * Mid-American Conference
 * MACA – (i) Military Aid to the Civil Authorities
 * MACE – (a) Multi-Agent Computing Environment
 * MACHO – (p) MAssive Compact Halo Object
 * MAD
 * (a) Magnetic Anomaly Detector
 * (s) Moroccan dirham (ISO 4217 currency code)
 * (a) Mutual Assured Destruction
 * MADD
 * (a) Mothers Against Drunk Driving
 * MyoAdenylate Deaminase Deficiency
 * (p) Multiply–Add
 * MAF – (i) Maintenance Action Form
 * MAFF - (a) Ministry of Agriculture, Forestry and Fisheries (various countries)
 * MAGIC – (a) Major Atmospheric Gamma-ray Imaging Cherenkov (telescope)
 * MAGNETAR – (p) Metaprogrammable AGent NETwork ARchitecture
 * MAGTF – (i) Marine Air-Ground Task Force
 * mah – (s) Marshallese language (ISO 639-2 code)
 * Mahasz – (p) Magyar Hanglemezkiadók Szövetsége (Hungarian, "Association of Hungarian Record Companies")
 * mal – (s) Malayalam language (ISO 639-2 code)
 * MALD – (a) Miniature Air-Launched Decoy
 * MANPADS – (p) MAN-Portable Air Defence System
 * MANPRINT – (p) MANpower and PeRsonnel INTegration
 * MAO
 * (i/a) Molėtų astronomijos observatorija (Moletai Astronomical Observatory)
 * (p) MonoAmine Oxidase
 * MAOI – (p) Monoamine oxidase inhibitor
 * MAP – (a) Management Action Plan (Corporate phrase)
 * MAPP - (a) Medical Assistance Premium Program
 * MAPS – (a) Monitoring Avian Productivity and Survivorship
 * MAQS – (a) Museum of the American Quilter's Society ("max")
 * mar – (s) Marathi language (ISO 639-2 code)
 * MAR – (s) Morocco (ISO 3166 trigram)
 * MarBEF – (p) Marine Biodiversity and Ecosystem Functioning
 * MARC
 * (a) MAchine Readable Cataloging (often also defined as MAchine Readable Code)
 * Mailing list ARChive
 * Maryland Area Regional Commuter train service
 * Massachusetts Animal Rights Coalition
 * Mid-America Regional Council
 * MARCENT – (p) United States Marine Forces Central Command
 * MARFORCC – (p) Marine Force Component Commander
 * MARRS – (a) Martyn Young, Alex Ayuli, Rudy Tambala, Russell Smith, and Steve Young (British electronic music act)
 * MAS – (i) NATO Military Agency for Standardization
 * MASAS – (a) Monte Agliale Supernovae and Asteroid Survey
 * Maser – (a) Microwave Amplification by Stimulated Emission of Radiation
 * MASH – (a) Mobile Army Surgical Hospital
 * MASINT – (p) Measurement And Signature Intelligence
 * MATREX – (p) Modeling Architecture for Technology, Research & EXperimentation
 * MATS – (a) U.S. Military Air Transport Service (1948–1966)
 * MAVS – (a/i) Mobile Artillery Vehicle System
 * MAW – (s) Malawi (IOC trigram, but not FIFA or ISO 3166)
 * MAX – (i) Meta-reasoning Architecture for "X"

MB

 * MB
 * (s) Manitoba (postal symbol)
 * Martinique (FIPS 10-4 territory code)
 * Medal of Bravery (Canada)
 * MBA
 * (i) Main Battle Area
 * Main Belt Asteroid
 * Master of Business Administration
 * MBI – (i) Moody Bible Institute
 * MBBL – (i) (U.S. Armor Center) Mounted Battlespace Battle Laboratory
 * MBCC – (i) Migratory Bird Conservation Commission (U.S.)
 * MBCS – (i) Multi-Byte Character Set
 * MBE
 * (p) Member of the Order of the British Empire
 * (i) Multistate Bar Examination (U.S.)
 * MBIDST – (i) Member of the British Institute of Dental and Surgical Technologists
 * MBM – (i) Meat and Bone Meal
 * MBR - (i) Master boot record
 * MbS – (i) Mohammad bin Salman (current crown prince of Saudi Arabia)
 * MBSE – (i) Model-based systems engineering
 * mbsf – metres below sea floor, a depth convention used in paleontology and oceanography
 * MBT – (i) Main Battle Tank
 * MBTA – (i) Massachusetts Bay Transportation Authority – Migratory Bird Treaty Act (U.S.)
 * MBTI – (i) Myers-Briggs Type Indicator

MC

 * mC – (s) Millicoulomb
 * MC
 * (s) Macau (FIPS 10-4 territory code)
 * (i) Master of Ceremonies
 * (s) Megacoulomb
 * (i) Military Cross (bravery award)
 * (s) Monaco (ISO 3166 digram)
 * (i) Mortar Carrier
 * (s) Eleven Hundred (in Roman numerals)
 * MCA
 * (i) Master of Computer Applications
 * Micro Channel Architecture
 * MultiChannel Analyzer
 * Music Corporation of America, the original name of the now-defunct MCA Inc.
 * (i) Malaysian Chinese Association
 * MCC
 * (i) Marylebone Cricket Club
 * Mission Control Center
 * Motor Control Center
 * Movement Control Centre
 * MCD
 * (i) Minimal Cerebral Dysfunction
 * Minor civil division (U.S. Census term)
 * MCDL – (i) Model Composition Definition Language
 * MCFT – (i) Modified Compression Field Theory
 * MCG – (i) Melbourne Cricket Ground
 * MC&G – (i) Mapping, Charting, and Geodesy
 * MCI – (i) Microwave Communications, Inc.
 * MCIS – (i) Mellon Collie and the Infinite Sadness
 * MCM – (i) Mine Counter-Measures
 * MCMV – (i) Mine Counter-Measure Vessel
 * MCNC
 * (i) Microelectronics Center of North Carolina
 * (i) Mixing Condensation Nucleus Counter
 * MCO
 * (i) Major Combat Operation
 * (s) Monaco (ISO 3166 trigram)
 * (s) Orlando International Airport (IATA code)
 * (i) Movement Control Officer
 * MCP
 * (i) Maintenance Collection Point
 * Male Chauvinist Pig
 * MCR – (i) My Chemical Romance
 * MCSF – (i) Marine Corps Security Forces
 * MCT – (i) Movement Control Team
 * MCTIS – (i) Mounted Co-operative Target Identification System
 * MCU
 * (i) Marine Corps University
 * Marvel Cinematic Universe
 * Medium close-up (camera direction in British TV scripts)
 * (p) Microcontroller unit
 * (i) Milk clotting units
 * Ming Chuan University
 * Minimum coded unit (digital imaging)
 * Multipoint control unit
 * Municipal Credit Union (New York)
 * MCWS – (i) Men's College World Series, the final phase of the NCAA Division I baseball tournament in the US

MD

 * Md – (s) Mendelevium
 * MD
 * (s) Fifteen Hundred (in Roman numerals)
 * Maryland (postal symbol)
 * (i) Medicinae Doctor (Doctor of Medicine/Medical Doctor)
 * Mentioned in Dispatches (military)
 * (s) Moldova (FIPS 10-4 country code; ISO 3166 digram)
 * MDA
 * (i) Main Defensive Action/Area
 * (s) Moldova (ISO 3166 trigram)
 * (i) Muscular Dystrophy Association
 * MDF
 * (i) Main distribution frame
 * Medium-density fiberboard
 * MDG
 * (s) Madagascar (ISO 3166 trigram)
 * (i) UN Millennium Development Goal
 * MDL – (s) Moldovan leu (ISO 4217 currency code)
 * MDM
 * (i) Michigan Dartmouth MIT telescope consortium
 * Master data management
 * MDMA – (i) MethyleneDioxy-MethylAmphetamine (also known as "Ecstasy")
 * MDNA – (p) Madonna's 12th studio album title (2012)
 * MDO – (i) Membership Driven Organisation
 * MDP – (i) Markov Decision Process
 * MDT – (i) Mountain Daylight Time (UTC−6 hours)
 * MDS
 * MDV – (s) Maldives (ISO 3166 trigram)
 * MDW
 * (s) Chicago Midway International Airport in Chicago (IATA airport code)
 * (i) Military District of Washington
 * (s) Minnesota, Dakota and Western Railway (AAR reporting mark)
 * (i) Mother’s Day Weekend

ME

 * Me – (s) Messerschmitt
 * ME
 * (s) Maine (postal symbol)
 * (i) Mechanical engineer[ing]
 * Medical examiner
 * Middle East
 * (s) Middle East Airlines (IATA code)
 * (i) Memory Effect – Myalgic Encephalomyelitis
 * MEA
 * (i) Maine Educational Assessment
 * Middle East Airlines
 * Millennium Ecosystem Assessment
 * Minimum en route altitude
 * Mono-ethanol Amine
 * Multilateral Environmental Agreement
 * MEAC – (a) Mid-Eastern Athletic Conference (ME-ac)
 * MEC
 * (s) Maine Central Railroad
 * Manta, Ecuador (IATA location identifier)
 * (i) Model European Council
 * Mountain East Conference
 * Mountain Equipment Co-op
 * MECC – (a) Minnesota Educational Computing Consortium (later Corporation, dissolved 1999)
 * MECCA – (a) Milwaukee Exposition Convention Center and Arena, a former name for the sports venue now known as UW–Milwaukee Panther Arena
 * MECO – (a) Main engine cutoff (NASA code for point in Space Shuttle assent when three main engines are shut down prior to External Tank (ET) separation)
 * MEDEVAC – (p) Medical evacuation
 * MEDLI
 * (a) Mars Science Laboratory Entry, Descent, and Landing Instrumentation
 * (a) Medical & Scientific Libraries of Long Island
 * (a) Model for Effluent Disposal using Land Irrigation
 * MEDS – (a) Mission Essential Data Set
 * MEF
 * (i) U.S. Marine Expeditionary Force
 * Minimum essential facility
 * Mission essential force
 * MEG – (i) MagnetoEncephaloGraphy
 * MEI – (i) Matsushita Electric Industrial Co., Ltd.
 * MEK
 * (i) Magyar Elektronikus Konyvtar
 * Message encryption key
 * (a) methyl ethyl ketone
 * (p) Mujahideen al-Khalq
 * MEL
 * (i) Maya Embedded Language
 * Michigan Electronic Library
 * MELT – (a) Metallic Line/Loop Test (ing)
 * MEM
 * (i) Message Exchange Mechanism
 * (p) Microelectromechanical
 * MEMS – (p) Microelectromechanical System
 * MENA – (i/a) Middle East and North Africa ("MEE-na" or "MEH-na")
 * MEO
 * (a) Medium Earth orbit
 * Most efficient organization
 * MEP
 * (i) Mechanical Electrical Plumbing
 * Member of the European Parliament
 * Missions étrangères de Paris (French for "Paris Foreign Missions")
 * Model European Parliament
 * MER – (i) Mars Exploration Rover
 * MERL – (i) Mitsubishi Electric Research Laboratories
 * MES
 * (i) Marconi Electronic Systems
 * Medium Edison screw
 * MESSENGER – (p) MErcury Surface, Space ENvironment, GEochemistry and Ranging
 * MET
 * (p) Meteorological
 * (a) Middle European Time
 * METAR – (p) [Meteorological] Aviation Routine weather report
 * METL – (i/a) Mission Essential Task List ("mettle")
 * METOC – (p) Meteorological and Oceanographic
 * METT-T – (a/i) Mission, Enemy, Terrain, Troops, and Time available (mnemonic)
 * METT-TC – (a/i) Mission, Enemy, Terrain [and weather], Troops [and support], Time [available] and Civilian considerations (mnemonic)
 * MEU
 * (i) U.S. Marine Expeditionary Unit
 * Maximum Expected Utility
 * MeV – (s) Megaelectronvolt
 * MEV
 * (i) Medical Evacuation Vehicle
 * Musica Elettronica Viva
 * MEX – (s) Mexico (ISO 3166 trigram)
 * MEZ – (i) Missile Engagement Zone
 * MES – (a) Manufacturing Execution Systems

MF

 * mF – (s) Millifarad
 * MF
 * (s) Mayotte (FIPS 10-4 territory code)
 * Megafarad
 * (a) Motherf***er (profanity)
 * MFG - (s) Manufacturing
 * MFSB – (i) Mother, Father, Sister, Brother (1970s Philadelphia studio musicians collective)
 * MFT
 * (i) Managed file transfer
 * Master File Table
 * Mean field theory
 * Media Foundation Transform
 * Micro Four Thirds (camera design standard)

MG

 * mg – (s) Malagasy language (ISO 639-1 code) – Milligram
 * Mg – (s) Magnesium – Megagram
 * MG – (i) Machine Gun – (s) Madagascar (ISO 3166 digram) – (s) Major General – (s) Mongolia (FIPS 10-4 country code) – (i) Morris Garage
 * MGA – (s) Malagasy ariary (ISO 4217 currency code)
 * MGB – (i) Medium Girder Bridge, Motor Gun Boat
 * MGM – (i) Metro Goldwyn Mayer – (s) Montgomery, Alabama (Airport Code)
 * MGPAM – My Gym Partner's a Monkey
 * MGS – (i) Mobile Gun System

MH

 * mh – (s) Marshallese language (ISO 639-1 code)
 * mH – (s) Millihenry
 * MH
 * (s) Marshall Islands (postal symbol; ISO 3166 digram)
 * Megahenry
 * Montserrat (FIPS 10-4 territory code)
 * (s) Malaysia Airlines (IATA code)
 * MHC – (i) Major Histocompatibility Complex
 * MHEV – Micro-Hybrid Electric Vehicle
 * MHHW – (i) Mean Higher High Water (nautical charts)
 * MHL – (s) Marshall Islands (ISO 3166 trigram)
 * MHLW – (i) Mean Higher Low Water (nautical charts)
 * MHRA – (i) (UK) Medicines and Healthcare products Regulatory Agency
 * MHW – (i) Mean High Water (nautical charts)
 * MHWN – (i) Mean High Water Neaps (nautical charts)
 * MHWS – (i) Mean High Water Springs (nautical charts)
 * MHz – (s) Megahertz

MI

 * mi – (s) Māori language (ISO 639-1 code)
 * Mi – (s) Mebi
 * MI
 * (s) Malawi (FIPS 10-4 country code)
 * Michigan (postal symbol)
 * Midway Islands (ISO 3166 digram; obsolete 1986)
 * (i) Military Intelligence
 * MIA
 * (i) Missing In Action
 * Miami International Airport (IATA code)
 * MIAA
 * (i) Maryland Interscholastic Athletic Association
 * Massachusetts Interscholastic Athletic Association
 * Michigan Intercollegiate Athletic Association
 * Mid-America Intercollegiate Athletics Association
 * MIB
 * (i) Men In Black
 * Mint In Box (Internet auction/trading listings)
 * MIC
 * (i) Military Industrial Complex
 * (i) Malaysian Indian Congress
 * MICE – (a) Meetings, Incentives, Conferences, Exhibitions tourism
 * MICLIC – (p) Mine Clearing Line Charge
 * MICOM – (p) Missile Command
 * MICV – (i) Mechanised Infantry Combat Vehicle
 * MID – (s) Midway Islands (ISO 3166 trigram; obsolete 1986)
 * MIDI – (a) Musical Instrument Digital Interface
 * MIDAS – (a) Man-machine Integration Design and Analysis System
 * MIDS – (i) Multi-Function Information Distribution System
 * MIFC – (a) Military Industrial Financial Complex
 * MIFG – (s) Shallow Fog (METAR Code)
 * MIFPC – (a) Military Industrial Financial Pharmaceutical Complex
 * MIKE – (a) Monitoring of Illegal Killing of Elephants
 * MIL – (i) Man-In-the-Loop
 * MIL-AASPEM – (i) Man-In-the-Loop AASPEM
 * MILAN – (p) Missile d´infanterie léger antichar (French, "Anti-Tank Light Infantry Missile")
 * MiLB – (p) Minor League Baseball
 * MILC – (a) Mirrorless interchangeable-lens camera
 * MILES – (a) Multiple Integrated Laser Engagement System (live combat simulation)
 * MILF
 * (i) Moro Islamic Liberation Front
 * (a) Mother I'd Like to F**k
 * MILSATCOM – (p) Military Satellite Communications
 * MILSET – (a) Mouvement International pour le Loisir Scientifique Et Technique (French, "International Movement for Leisure Activities in Science and Technology")
 * MILSTRIP – (p) Military Standard Requisitioning and Issue Procedure DLMSO MILSTRIP Manual
 * Mimaropa – (p) Mindoro, Marinduque, Romblon, Palawan (a region in the Philippines)
 * MIMOSA – (a) MIcroMeasurements Of Satellite Acceleration
 * MIMPT – (i) Member of the Institute of Maxillofacial Prosthetists and Technologists
 * MIP
 * (a) Multilateral Interoperability Programme
 * Multiple Identity Poster
 * MIPC – (a) Military Industrial Pharmaceutical Complex
 * MIRA – (a) MILAN Infra-Red Acquisition (thermal sight)
 * MIRV – (a) Multiple Independent Reentry Vehicle
 * MIS
 * (a) Management Information Systems
 * Museum Information System
 * MISREP – (p) Mission Report
 * MISSI – (a) Multilevel Information System Security Initiative
 * MIT
 * (i) Massachusetts Institute of Technology
 * methylisothiazoline
 * Milli Istihbarad Teskilati (Intelligence service of Turkey)
 * MITL – (i) Man-In-The-Loop
 * MITS – see entry

MJ

 * mJ – (s) Millijoule
 * MJ
 * (s) Megajoule
 * (i) Michael Jordan
 * (i) Michael Jackson
 * (i) Mary Jane Watson (Spider-Man character)
 * MJD – (i) Modified Julian Day
 * MJF – (i) Maxwell Jacob Friedman, American professional wrestler (who currently performs as "MJF")
 * MJP – (i) Military Judgement Panel

MK

 * mk – (s) Macedonian language (ISO 639-1 code)
 * mK – (s) Millikelvin
 * Mk - (s) Mark (US weapon designation), as in Mk 18 MOD 0 CQBR
 * MK
 * (s) Air Mauritius (IATA code)
 * Macedonia (ISO 3166 digram; FIPS 10-4 country code)
 * (i) Mandalskameratene (Norwegian football club)
 * (s) Megakelvin
 * (i) Milton Keynes
 * Missionary Kids
 * Mortal Kombat (1992 video game)
 * Mortal Kombat (2011 video game)
 * mkd – (s) Macedonian language (ISO 639-2 code)
 * MKD
 * (s) Macedonian denar (ISO 4217 currency code)
 * North Macedonia (ISO 3166 trigram)
 * MKG – (i) Michael Kidd-Gilchrist (American basketball player)
 * MKO – (i) Mojahedin-e-Khalq Organization (Persian, "People's Mujahedin of Iran")
 * MKS
 * (i) Metre–Kilogram–Second (system of units)
 * (p) MKS Inc. software company
 * MKSA – (i) Metre–Kilogram–Second–Ampere (system of units)
 * MKT
 * (i) Missouri-Kansas-Texas Railroad (1865–1989)
 * Mortal Kombat Trilogy
 * Short form of Marketing

ML

 * ml – (s) Malayalam language (ISO 639-1 code)
 * mL – (s) Millilitre
 * ML
 * (s) Mali (FIPS 10-4 country code; ISO 3166 digram)
 * (i) Maximum Likelihood
 * (s) Megalitre
 * MLA
 * (i) Martial Law Administration of Bangladesh
 * Master of Landscape Architecture
 * Medical Library Association
 * Member of Legislative Assembly
 * Modern Language Association
 * Mutual legal assistance treaty
 * Myelosis Leucemica Acuta
 * MLB
 * (i) Major League Baseball
 * (s) Melbourne Orlando International Airport (IATA code)
 * MLC – (i) Member of the Legislative Council (in India)
 * MLE – (i) Maximum likelihood estimation
 * mlg – (s) Malagasy language (ISO 639-2 code)
 * MLG
 * (i) Major League Gaming
 * (i) Main Landing Gear
 * MLHW – (i) Mean Lower High Water (nautical charts)
 * MLI – (s) Mali (ISO 3166 trigram)
 * MLK – (i) Martin Luther King Jr.
 * MLL – (i) Major League Lacrosse
 * MLLW – (i) Mean Lower Low Water (nautical charts)
 * MLP – My Little Pony
 * MLR
 * (i) Medical Loss Ratio
 * MLRS – (i) Multiple-Launch Rocket System
 * MLS
 * (i) Major League Soccer
 * Multiple Listing Service
 * Multilevel security
 * MLSE
 * (i) Maple Leaf Sports & Entertainment (owner of several Toronto-based sports teams)
 * Maximum likelihood sequence estimation
 * MLSR – (i) Missing, Lost or Stolen Report
 * mlt – (s) Maltese language (ISO 639-2 code)
 * MLT – (s) Malta (ISO 3166 trigram)
 * MLVW – (i) Medium Logistics Vehicle, Wheeled
 * MLW
 * (i) Major League Wrestling (American professional wrestling promotion)
 * Mean Low Water (nautical charts)
 * MLWN – (i) Mean Low Water Neaps (nautical charts)
 * MLWS – (i) Mean Low Water Springs (nautical charts)

MM

 * mm – (s) Millimetre
 * Mm – (s) Megametre
 * MM – (i) Military Medal – (s) Myanmar (ISO 3166 digram) – Two Thousand (in Roman numerals)
 * MMA – (i) Mixed martial arts – Moving Mechanical Assembly
 * MMC – (p) Machinist's Mate, Chief (USN rating) – (i) Materiel Management Centre
 * MMCM – (p) Machinist's Mate, Master Chief (USN rating) – (i) Magnetic Mine Counter Measure
 * MMCS – (p) Machinist's Mate, Senior Chief (USN rating)
 * MMEV – (i) Multi-Mission Effects Vehicle
 * MMI – (i) Man-Machine Interface
 * MMI – (i) McLean Meditation Institute
 * MMIC – (i) Mindfulness & Meditation Instructor, Certified
 * MMIC – (i) McLean Meditation Institute Certified
 * MMI – (i) Magical MonkeyZ Inc.
 * MMIO – (i) Memory-mapped I/O
 * MMK – (s) Burmese kyat (ISO 4217 currency code)
 * MMO – (i) Massively Multiplayer Online (computer game)
 * MMOR – (i) Master of Management in Operations Research
 * MMORPG – (i) Massively multiplayer online role-playing game
 * MMPR – Mighty Morphin Power Rangers
 * MMR – (i) Measles, Mumps and Rubella vaccine – (s) Myanmar (ISO 3166 trigram)
 * MMS – (i) Multimission Modular Spacecraft
 * MMU – (i) Manchester Metropolitan University – (i) Manned Manoeuvring Unit
 * MMW – (p) Millimetre Wave (radar, from "mm Wave")

MN

 * mn – (s) Mongolian language (ISO 639-1 code)
 * mN – (s) Millinewton
 * Mn – (s) Manganese
 * MN – (s) Meganewton – Minnesota (postal symbol) – Monaco (FIPS 10-4 country code) – Mongolia (ISO 3166 digram)
 * MNB – (p) Multinational Brigade
 * MNB C – (p) Multinational Brigade Centre (KFOR)
 * MND – (i) Motor Neurone Disease – (p) Multinational Division
 * MNE – (s) Montenegro (ISO 3166 trigram)
 * MNG – (i) Multiple-image Network Graphics – (s) Mongolia (ISO 3166 trigram)
 * MNMF – (i) Multi-National Maritime Force
 * MNP – (s) Northern Mariana Islands (ISO 3166 trigram)
 * MNS – (i) Mission Needs Statement
 * MNT – (p) Molecular nanotechnology – (s) Mongolian tugrik (ISO 4217 currency code)

MO

 * mo – (s) Moldovan language (ISO 639-1 code)
 * Mo – (s) Molybdenum
 * MO – (s) Macau (ISO 3166 digram) – (i) Medical Officer – (s) Missouri (postal symbol) – (i) modus operandi (Latin, "mode of operation") – (s) Morocco (FIPS 10-4 country code) [mutual oral]
 * MOA – Museum of Art (Brigham Young University)
 * MOAB – (a) Massive Ordnance Air Blast (official) – Mother Of All Bombs (slang)
 * MOB – (i) Man Over Board – Marching Owl Band – Movable Object Block
 * MOC – (i) Macedonian Orthodox Church – Measure Of Capability – Mission Operations Centre – My Own Creation (Lego)
 * MOCAS – (a) Mechanization Of Contract Administration Services
 * MoD – (i) Ministry of Defence (United Kingdom) and various other countries
 * MOD – (i) Magneto-optical disc – Masters of Deception – Minimum Object Distance – Multiple Organ Dysfunction
 * MoDAF – (p) Ministry of Defence Architecture Framework ("moh-daff")
 * modem – (p) Modulator-Demodulator
 * ModSAF – (p) Modular Semi-Automated Forces (military simulation)
 * Moe – (a) Marvel of entertainment
 * MOE – (i) Measure Of Effectiveness
 * MOF – (a/i) Ministry of Finance (Japan)
 * MOFA – (a/i) Ministry of Foreign Affairs (Japan)
 * MOH – (a/i) Medal of Honor – Music On Hold
 * MOID – (i) Minimum Orbital Intersection Distance
 * MOJWA – (i) Movement for Oneness and Jihad in West Africa
 * mol – (s) Moldovan language (ISO 639-2 code) – mole (unit)
 * MOLO – (a) Mobile Other Licensed Operator (UK)
 * MoM – (a) Multiple of the median
 * MOM – (a) Message-oriented middleware
 * MOM – (a) Master's Degree in Oriental medicine
 * MoMA – (a) Museum of Modern Art (NYC)
 * mon – (s) Mongolian language (ISO 639-2 code)
 * MOND – (p) Modified Newtonian Dynamics
 * MOO – (i) Measure Of Outcome
 * MOOTW – (p) Military Operations Other Than War ("moot-double-you")
 * MOP – (s) Macau pataca (ISO 4217 currency code) – (i) Measure Of Performance
 * MOPE – (a) Ministry of Population and Environment (Nepal) – Most Oppressed People Ever (politics)
 * MOPP – (i/a) Mission-Oriented Protective Posture
 * MORP – (a) Meteorite Observation and Recovery Project
 * MORS – (i) Military Operations Research Society
 * MOS – (i) Military Occupational Specialty – (a) Mit Out Sound / Motor Only Sync – (i) Mobile Object System – Model Output Statistics – Multiplayer Online Services - (a) Mean Opinion Score
 * MOS-CQ - (a) Mean Opinion Score - Conversational Quality (ITU-T P.800.1)
 * MOS-LQ - (a) Mean Opinion Score - Listening Quality (ITU-T P.800.1)
 * MOSFET – (a) Metal-Oxide-Semiconductor Field-Effect Transistor
 * MOSS – (p) MObile Submarine Simulator – (a) Moving Object Support System
 * MOT – (i) Ministry of Transport (UK)
 * MOTA – (i) Member of the Orthodontic Technicians Association
 * MOTESS – (a) Moving Object and Transient Event Search System
 * MOTO – (a) Mail Order / Telephone Order – Master of the obvious
 * MOU – (i) Memorandum Of Understanding
 * MOUT – (i) Military Operations in Urban[ized] Terrain
 * MOVES – (a) Modeling, Virtual Environments, and Simulation Institute
 * MOW – (i) Maintenance of way (also MW)
 * MOZ – (s) Mozambique (ISO 3166 trigram)

MP

 * MP – (i) Magic points – (s) Mauritius (FIPS 10-4 country code) – (i) Member of Parliament – Military Police – Missouri Pacific – (s) Northern Mariana Islands (postal symbol; ISO 3166 digram)
 * mPa – (s) Millipascal
 * MPa – (s) Megapascal
 * MPA - Master of Public Administration
 * MPA – (i) Maritime Patrol Aircraft
 * MPAA – (i) Motion Picture Association of America
 * MPC – (i) Minor Planet Center – Minor Planet Circular
 * MPC – (i) Military Payment Certificate
 * MPEC – (i) Minor Planet Electronic Circular
 * MPEG – (a) Motion Pictures (Coding) Experts Group
 * MPEV – (i) Multi-Purpose Engineering Vehicle
 * MPF – (i) Maritime Prepositioning Force
 * MPFC – (i) Medial PreFrontal Cortex
 * MPG - (i) Miles Per Gallon
 * MPMC – (i) Medial PreMotor Cortex
 * MPSI – (i) Member of the Pharmaceutical Society of Ireland
 * MPSoC – (i) MultiProcessor System-on-Chip
 * MPSRON – (p) Maritime Propositioning Ship Squadron

MQ

 * MQ
 * (s) Martinique (ISO 3166 digram) – Midway Islands (FIPS 10-4 territory code)
 * (s) Multi-mission Unmanned Aerial Vehicle (US tri-service aircraft designator)

MR

 * mr – (s) Marathi language (ISO 639-1 code)
 * MR – (s) Mauritania (FIPS 10-4 country code; ISO 3166 digram)
 * (i) Model Railroader Magazine
 * MR-ATGW – (i) Medium-Range Anti-Tank Guided Weapon
 * MRAV – (i) Multi-Role Armoured Vehicle
 * MRBM – (i) Medium Range Ballistic Missile
 * MRC – (i) Maintenance Requirements Card
 * MRD – (i) Motorized Rifle Division
 * MRE – (i) Meal Ready to Eat (U.S. military rations)
 * MRGO – (i) Mississippi River–Gulf Outlet Canal (also referred to as MR-GO or "Mr. Go")
 * MRGW – (i) Medium-range guided weapon
 * mri – (s) Māori language (ISO 639-2 code)
 * MRI – (i) Magnetic resonance imaging
 * MRL – (i) Multiple rocket launcher
 * (i) Montana Rail Link
 * MRO
 * (i) Maintenance, repair and operations
 * Mars Reconnaissance Orbiter
 * (s) Mauritanian ouguiya (ISO 4217 currency code)
 * MRPharmS – (i) Member of the Royal Pharmaceutical Society (Great Britain)
 * MRR – My Restaurant Rules
 * MRS – (i) Magnetic Resonance Spectroscopy
 * MRSA – (i/a) Methicillin-resistant Staphylococcus aureus (sometimes pronounced "MER-sa")
 * MRT
 * (i) Mass Rapid Transit — used as either an official or unofficial name for metro systems in Singapore, Kaohsiung, Bangkok, Taipei, Chennai, and Delhi
 * (s) Mauritania (ISO 3166 trigram)
 * MRTFB – (i) U.S. Major Range and Test Facility Base

MS

 * ms
 * (s) Malay language (ISO 639-1 code)
 * Millisecond
 * mS – (s) Millisiemens
 * Ms – (s) Megasecond
 * MS
 * (i) mano sinistra (Latin, "left hand")
 * (p) manuscript
 * (i) Master of Science
 * (s) Megasiemens
 * (p) Microsoft (sometimes M$)
 * (s) Mississippi (postal symbol)
 * Montserrat (ISO 3166 digram)
 * (i) Multiple Sclerosis
 * M&S
 * (i) Modelling & Simulation
 * Marks & Spencer
 * MSA – (s) Malay language (ISO 639-2 code)
 * MSB
 * (i) Main Support Battalion
 * Most Significant Bit (or Byte)
 * MSD – (i) Minimum Safe Distance
 * MSDB – (i) Multi Source Data Base
 * MSDE
 * (i) Maryland State Department of Education
 * (p) Microsoft Data[base] Engine
 * Microsoft SQL Server 2000 Desktop Engine
 * (i) Military Scenario Development Environment
 * Mission Simulation Dynamic Engine
 * MSDL – (i) Military Scenario Definition Language
 * MSE – (i) Multiple Subscriber Element
 * MSFS - (i) Microsoft Flight Simulator (flight simulator series)
 * MSEC – (p) Message Security Encryption Code ("emm-sec")
 * MSG
 * (i) MonoSodium Glutamate
 * Madison Square Garden (either the 1879, 1890, 1925, or current versions of the venue)
 * MSH
 * (i) Medium Support Helicopter
 * Mount St. Helens
 * MSI
 * (i) Micro-Star International
 * (p) Multispectral imagery
 * MSIE
 * (i) Microsoft Internet Explorer
 * Master of Science in Industrial Engineering
 * MSL
 * (i) Mars Science Laboratory
 * Mean Sea Level
 * (p) Missile
 * MSLP – (i) Mean Sea Level Pressure
 * MSM
 * (p) Mainstream media
 * (i) Men who have sex with men
 * Mount St Mary's School
 * MSN
 * (i) Microsoft Network
 * Master of Science in Nursing
 * MSNBC – (i) Microsoft National Broadcasting Company Cable news channel (see also msnbc.com)
 * MSO – (i) Multiple System Operator
 * MSP
 * Member of the Scottish Parliament
 * (i) Minneapolis–Saint Paul - Twin cities in Minnesota
 * (s) Minneapolis–Saint Paul International Airport (IATA code)
 * MSPA
 * (p) Migrant and Seasonal worker Protection Act
 * (a) MS Paint Adventures
 * MSPB – (i) Merit Systems Protection Board
 * MSR
 * (i) Main Supply Route
 * Module Service Record
 * (s) Montserrat (ISO 3166 trigram)
 * (i) Motor Schlepp Regulung
 * Mountain Safety Research (outdoor supplies manufacturer)
 * MSSA
 * Member of the Order of the Star of South Africa
 * (i) Methicillin-susceptible Staphylococcus aureus
 * (i) Military Selective Service Act
 * (i) Military-style semi-automatic
 * (i) Mind Sports South Africa
 * (i) Montreal Student Space Associations
 * MSSA Chemical Company, formerly known as Métaux Spéciaux.
 * MST
 * (i) Madison Symmetric Torus
 * Mountain Standard Time (UTC−7 hours)
 * Maastricht Aachen Airport (IATA code]]
 * MST3K or MST3k – (i) Mystery Science Theater 3000
 * MSU
 * (i) Michigan State University
 * Montana State University
 * Mountain State University
 * Lomonosov Moscow State University (Russia, a.k.a. MGU)

MT

 * mt – (s) Maltese language (ISO 639-1 code)
 * mT – (s) Millitesla
 * Mt – (s) Meitnerium
 * MT
 * (s) Malta (FIPS 10-4 country code; ISO 3166 digram)
 * Megatesla
 * Montana (postal symbol)
 * (i) Motor Transport (military)
 * MTA
 * (i) Metropolitan Transportation Authority (Boston) (now Massachusetts Bay Transportation Authority)
 * Metropolitan Transportation Authority
 * MTBF – (i) Mean time between failures
 * MtF – (i) Male-to-female transsexual
 * MTF
 * (i) Magnetized target fusion
 * Medical Treatment Facility
 * Message Text Format
 * Modulation transfer function (optics)
 * MTG – (i) Magic: The Gathering
 * MTL
 * (s) Maltese lira (ISO 4217 currency code)
 * (i) Mean Tide Level (nautical charts)* MTM – (i) Methods-Time Measurement
 * MTOE – (p) Modified Table of Organization and Equipment ("emm-toe")
 * MTP
 * (i) Maritime Tactical Publication
 * Materiel Transfer Plan
 * Mission Training Plan
 * MTQ – (s) Martinique (ISO 3166 trigram)
 * MTR
 * (i) Main and Tail Rotor (helicopter type)
 * Mass Transit Railway (Hong Kong metro system)
 * Military-Technological Revolution
 * MTS
 * (i) Maintenance Training System
 * Manitoba Telephone System and Manitoba Telecom Services, former names of Bell MTS
 * Michigan Terminal/Timesharing System
 * Movement Tracking System
 * Multichannel television sound
 * Multi-Technical Services
 * MTT – (p) Methylthiazol tetrazolium (assay)
 * MTU
 * (i) Tankovei Mostoukladchik (Russian Танковый Мостоукладчик, "Tank Bridge-Layer") †
 * (i) Motoren- und Turbinen-Union (German engine manufacturer, now split into MTU Friedrichshafen and MTU Aero Engines
 * MTV
 * (i) MainosTeleVisio (Finnish commercial TV company)
 * Music TeleVision
 * MTVL – (i) Mobile Tracked Vehicle, Light
 * MTWS – (i) MAGTF Tactical Warfare System

MU

 * MU
 * (s) Mauritius (ISO 3166 digram)
 * (s) Oman (FIPS 10-4 country code; from Muscat)
 * Manchester United (British football club)
 * MUA
 * (i) Meritorious Unit Award
 * Military Utility Assessment
 * (i) Make-up Artist
 * MUR – (s) Mauritius rupee (ISO 4217 currency code)
 * MUS – (s) Mauritius (ISO 3166 trigram)

MV

 * mV – (s) Millivolt
 * MV – (s) Maldives (FIPS 10-4 country code; ISO 3166 digram) – Megavolt – (i) Motor Vehicle – Motor Vessel
 * MVC – (i) Missouri Valley Conference
 * MVFC – (i) Missouri Valley Football Conference
 * MVNO – (i) Mobile virtual network operator
 * MVP – (i) Most Valuable Player
 * MVR – (s) Maldivian rufiyaa (ISO 4217 currency code)

MW

 * mW – (s) Milliwatt
 * MW
 * (i) Maintenance of way (also MOW)
 * (s) Malawi (ISO 3166 digram)
 * (i) Medium Wave (radio)
 * (s) Megawatt
 * (i) Mountain West (Conference) (formal initialism since July 2011)
 * MWC
 * (i) Maritime Warfare Centre (various nations)
 * Mountain West Conference (still used informally, although the league has adopted "MW")
 * MWESH – (p) Machismo Wizards Extended SHelter (operating system)
 * MWI – (s) Malawi (ISO 3166 trigram)
 * MWK – (s) Malawian kwacha (ISO 4217 currency code)
 * MWOA – (i) Mount Wilson Observatory Association
 * MWR – (i) Morale, Welfare, and Recreation
 * MWTB - (a) Mounted Warfare Test Bed

MX

 * MX – (a) Mail Exchange – (s) Mexico (FIPS 10-4 country code; ISO 3166 digram) – (p) Missile eXperimental
 * MXN – (s) Mexican peso (ISO 4217 currency code)

MY

 * my – (s) Burmese language (ISO 639-1 code)
 * MY – (s) Malaysia (FIPS 10-4 country code; ISO 3166 digram)
 * mya – (s) Burmese language (ISO 639-2 code) – (i) million years ago
 * MYOB – (i) Mind Your Own Business
 * MYR – (s) Malaysian ringgit (ISO 4217 currency code)
 * MYS – (s) Malaysia (ISO 3166 trigram)
 * MYT – (s) Mayotte (ISO 3166 trigram)

MZ

 * MZ – (i) Mach-Zehnder (interferometer) – (s) Magnetic Azimuth – (i) Move, Zig (Zero Wing) – (s) Mozambique (FIPS 10-4 country code; ISO 3166 digram)
 * MZN – (s) Mozambique metical (ISO 4217 currency code)