| Abbreviation | Definition |
|---|---|
| MPYS | Mornington Peninsula Youth Service |
| MPZ | MediaPro Zone |
| MPZ | Muggle Pride Zone |
| MQB | McElroy, Quirk, and Burch Certified Public Accountants |
| MQB | McQuade & Bannigan, Inc. |
| MQC | Maritime Quality Consultants, Inc. |
| MQC | MicroQuest Company |
| MQH | Magnolia Quarter Horses |
| MQH | Mettrick Quarter Horses |
| MQI | Market Quality Industries, Inc. |
| MQI | Missenard-Quint Industries |
| MQI | Moore Quality, Incorporated |
| MQL | Medicine Quantale Limited |
| MQR | Museum Quality Restorations |
| MR | Manufacture Royale |
| MR | Mecham's Racing |
| MR | Merchant Republic |
| MR | Mitsubishi Racing |
| MRA | Material Risk Assessment |
| MRAC | Mortgage Risk Assessment Corporation |