| MSI | First year of Military Science 
| Others |
| MSI | Italian Social Movement
| Others |
| MSI | MAC Satisfaction Indicator
| Others |
| MSI | Machine Sequence Imaging
| Others |
| MSI | Macintyre Strater Internatational
| Others |
| MSI | Magnetic Source Imaging
| Others |
| MSI | Maharishi Sadashiva Isham
| Others |
| MSI | Maintenance Significant Item
| Others |
| MSI | Major Service Interruption
| Others |
| MSI | Man-System Integration
| Others |
| MSI | Managed Service Identity
| Others |
| MSI | Management of Social Interaction
| Others |
| MSI | Management Services Incorporated
| Others |
| MSI | Management Services of Illinois
| Others |
| MSI | Management Systems International
| Others |
| MSI | Mando Softtech India
| Others |
| MSI | Manufacturer Specific Information
| Others |
| MSI | Manufacturing Skills Institute
| Others |
| MSI | Manufacturing Solutions Inc
| Others |
| MSI | Manure Spreading Index
| Others |
| MSI | Marine Safety Information
| Others |
| MSI | Marine Science Institute
| Others |
| MSI | Maritime Safety Information
| Others |
| MSI | Market Standard Indicator
| Others |
| MSI | Marketing Science Institute
| Others |
| MSI | Maruti Suzuki India
| Company, Transport, Automobile |
| MSI | Masonry and Structural Improvements
| Others |
| MSI | Material Sustainability Index
| Others |
| MSI | Materials Sustainability Index
| Others |
| MSI | Maximum Symbol Inversion
| Others |
| MSI | Mayfair Storage Interconnect
| Others |
| MSI | Mean Squared Intercept
| Others |
| MSI | Measurement Systems International
| Others |
| MSI | Measurements Standards and Intercomparisons
| Others |
| MSI | Mechanical Systems Inc
| Others |
| MSI | Media Services Interface
| Others |
| MSI | Medical Services Insurance
| Others |
| MSI | Medium Scale Integrated
| Others |
| MSI | Medium Scale Integration
| Others |
| MSI | Medium System Integrated
| Others |
| MSI | Medium-Scale Integration
| Others |
| MSI | MedShare International
| Others |
| MSI | Meeting Services Inc
| Others |
| MSI | Member of Securities Institute
| Others |
| MSI | Meritorious Service Increase
| Others |
| MSI | Message Service Interface
| Others |
| MSI | Message Signaled Interrupt
| Others |
| MSI | Message Stream Interface
| Others |
| MSI | Message-Signaled Interrupt
| Others |
| MSI | Metabolomics Standards Initiative
| Others |
| MSI | Metapath Software International
| Others |
| MSI | Michigan State Industries
| Others |
| MSI | Micro Star International
| Others |
| MSI | Micro Start International
| Others |
| MSI | Micro Structured Implant
| Others |
| MSI | Micro Systems International
| Others |
| MSI | Micro-Star International
| Others |
| MSI | Microbial Sciences Initiative
| Others |
| MSI | Microelectronics Society Of India
| Others |
| MSI | Microprocessor Slave Interface
| Others |
| MSI | MicroSatellite Instability
| Others |
| MSI | microsatellite instability If
| Others |
| MSI | Microsoft Installer
| Others |
| MSI | Microsoft Software Installation
| Others |
| MSI | Microsoft System Installer
| Others |
| MSI | Mid Season Invitational
| Others |
| MSI | Middle School Instruction
| Others |
| MSI | Migration Series Instruction
| Others |
| MSI | Mindless Self Indulgence
| Others |
| MSI | MineSweeper, In-shore
| Others |
| MSI | Minnesota Supercomputing Institute
| Others |
| MSI | Minority Serving Institution
| Others |
| MSI | Mobile Services Initiative
| Others |
| MSI | Mobile Software Initiative
| Others |
| MSI | Mobile Station Identifier
| Others |
| MSI | Mobilized Software Initiative
| Others |
| MSI | Modified Supplemental Instruction
| Others |
| MSI | Modified Surface Index
| Others |
| MSI | Molecular Simulations, Inc.
| Others |
| MSI | Molecular Simulations, Incorporated
| Others |
| MSI | Monseigneur Sencie Institute
| Others |
| MSI | Montgomery Soccer Inc
| Others |
| MSI | Mostra Scambio Imola
| Others |
| MSI | Motor and Sport Institute
| Others |
| MSI | Motor Sports International
| Others |
| MSI | Motorola Solutions Inc
| Others |
| MSI | Mountain Studies Institute
| Others |
| MSI | Much Salt Incoming
| Others |
| MSI | Multi Sensor Integration
| Others |
| MSI | Multi Service Interface
| Others |
| MSI | Multi Source Inventory
| Others |
| MSI | Multi-Spectral Imagery
| Others |
| MSI | Multiple Source of Income
| Others |
| MSI | Multiple Sources Of Income
| Others |
| MSI | Multiple Spark Ignition
| Others |
| MSI | Multispectral Imagery
| Others |
| MSI | Multispectral Solutions, Inc.
| Others |
| MSI | Multispeed Internal Clock
| Others |
| MSI | Music or Speech Item
| Others |
| MSI | My Scrotum Itches
| Others |