| Abbreviation | Definition |
|---|---|
| MRTS | Mass Rapid Transit System |
| MRTS | Mass Rapid Transit System (Chennai) |
| MRU | Movement Release Unit |
| MRV | Mechanized Recovery Vehicle |
| MRV | Missile Reentry Vehicle |
| MRV | Mission Robotic Vehicle |
| MRV | Mobile Rec Vehicle |
| MRV | Mobile Roadway Vehicle |
| MRV | Modular Robotic Vehicle |
| MRV | Multiple Reentry Vehicles |
| MS | Multi Speed |
| MSA | Marine Science Activities |
| MSA | Metro Service Area |
| MSA | Minimum Safe Altitude |
| MSA | Moving Straight Ahead |
| MSAW | Minimum Safe Altitude Warning |
| MSB | Maritime Subsidy Board |
| MSC | Marine Safety Council |
| MSC | Mechanical Speed Control |
| MSD | Marine Sanitation Device |