| Abbreviation | Definition |
|---|---|
| MCWS | the Major Challenges of Water Scarcity |
| MDCAT | Multi-Layer Data Community Action Tool |
| MDDL | Minimum Draw Down Level |
| MDEP | Maine Department of Environmental Protection |
| MDEQ | Michigan Department of Environmental Quality |
| MDEQ | Montana Department of Environmental Quality |
| MDWS | Ministry of Drinking Water and Sanitation |
| MEA | Midwest Environmental Advocates |
| MEAL | Malmsbury Environmental Action League |
| MEAN | Mossville Environmental Action Now |
| MEAS | Merseyside Environmental Advisory Service |
| MEC | Midwest Environmental Control |
| MECC | Midwest Environmental Compliance Conference |
| MEDA | Mars Environmental Dynamics Analyser |
| MEDA | Mars Environmental Dynamics Analyzer |
| MEDU | Medicinal and Environmental Defense Unit |
| MEEA | Midwest Environmental Enforcement Association |
| MEELS | Mandatory Energy Efficiency Labeling Scheme |
| MEELS | Mandatory Energy Efficiency Labelling Scheme |
| MEEN | Manchester Environmental Education Network |