| Abbreviation | Definition |
|---|---|
| MISIS | Micro Integrated Storm Information System |
| MISIS | Micro-Integrated Storm Information System |
| MISO | Monterey Inner Shelf Observatory |
| MIUU | Meteorological Institute of the University of Uppsala, Sweden |
| MIZ | Marginal Ice Zone |
| MIZEX | Marginal Ice Zone Experiment |
| MIZEX | Mixed Layer Depth |
| MLT | Mean Low Tide |
| MLW | Mean Low Water |
| MLWV | Mid- Level Water Vapor |
| MM | Master Mariner |
| MM | Mesoscale Model |
| MM4 | Mesoscale Meteorological Model -- Version 4 |
| MM5 | Mesoscale Model version 5 |
| MMC | Marine Mammal Commission |
| MMM | Meso-scale and Micro-scale Meterology |
| MMM | Mesoscale and Micro-scale Meterology |
| MMPA | Marine Mammal Protection Act |
| MMS | Minerals Management Service |
| MNI | Member of the Nautical Institute |