| MAR | Atos MARkham Pan Am / Parapan Am Centre 
| Others |
| MAR | La Chinita International Airport
| Others |
| MAR | Mainline Alternative Route
| Others |
| MAR | Maintenance Action Request
| Others |
| MAR | Managed Arrival Reservoir
| Others |
| MAR | Management Assessment Review
| Others |
| MAR | Maracaibo La Chinita International Airport, Maracaibo, Venezuela
| Others |
| mar | Marathi
| Others |
| MAR | Marble
| Others |
| Mar | March
| Others |
| MAR | Marchen Awaken Romance
| Others |
| MAR | Marcia
| Others |
| MAR | Market Access Reporting
| Others |
| MAR | Maryland Association of Realtors
| Others |
| MAR | Massachusetts Association of Realtors
| Others |
| MAR | Master Address Repository
| Others |
| MAR | Master of Arts in Religion
| Others |
| MAR | Material Approach Request
| Others |
| MAR | maternal antibody related autism
| Others |
| MAR | Matrix Attachment Region
| Others |
| MAR | Maximum Allowable Rent
| Others |
| MAR | Mayland Amateur Radio
| Others |
| MAR | Medical Administration Report
| Others |
| MAR | Medication Administration Record
| Others |
| MAR | Medication Administration Records
| Others |
| MAR | Medications And Regulations
| Others |
| MAR | Memory Address Register
| Others |
| MAR | Memory Attribute Register
| Others |
| MAR | Mercury Arc Rectifier
| Others |
| MAR | Mercury Marquis
| Others |
| MAR | Messing Around Racing
| Others |
| MAR | METOC Assistance Request
| Others |
| MAR | Mick Andrews Replica
| Others |
| MAR | Micro-Assault Rifle
| Others |
| MAR | Microprogram Address Register
| Others |
| MAR | Microsoft Access Report
| Others |
| MAR | MicroSoft Access Report shortcut
| Others |
| MAR | Mid Atlantic Region
| Others |
| MAR | Mid-Air Retrieval
| Others |
| MAR | Mid-Atlantic Ridge
| Others |
| MAR | Midrange Access Routers
| Others |
| MAR | Midwest Automotive Recyclers
| Others |
| MAR | Minimal Acceptable Return
| Others |
| MAR | Minimally Attended Radar
| Others |
| MAR | Minimum Angle of Resolution
| Others |
| MAR | Minor Access Road
| Others |
| MAR | Minorities at Risk
| Others |
| MAR | Misinformation Arrogance and Retaliation
| Others |
| MAR | Missile Achievable Range
| Military, Defence, Weapon, Measurement Unit, Distance |
| MAR | Missing At Random
| Others |
| MAR | Mission Analysis Room
| Others |
| MAR | Mississippi-Atchafalaya River
| Others |
| MAR | Mixed Agglutination Reaction
| Others |
| MAR | Mixed Antiglobulin Reaction
| Others |
| MAR | Mobile Access Router
| Others |
| MAR | Mobile Autonomous Robot
| Others |
| MAR | Modernization and Associated Restructuring
| Others |
| MAR | Modified Aspect Ratio
| Others |
| MAR | Monthly Activities Reporting
| Others |
| MAR | Mopar Alley Rally
| Others |
| MAR | Moteur Arriere
| Others |
| MAR | Multiple Antibiotic Resistance
| Others |
| MAR | Museo Storico Alfa Romeo
| Others |
| MAR | Museum of the American Railroad
| Others |
| MAR | Musically Automated Robot
| Others |
| MAR | Superior Court Mandatory Arbitration Rules
| Others |
| MAR | VAX Macro Assembly program
| Others |