| Abbreviation | Definition |
|---|---|
| MDRX | AllScripts, Inc. |
| MDSC | MediScience Technology Corporation |
| MDSEF | Madison Enterprises Corporation |
| MDSI | M D S I Mobile Data Solutions, Inc. |
| MDSLF | Medis E, LTD. |
| MDSN | Madison Gas & Electric Company |
| MDSO | Medidata Solutions |
| MDST | Mid State Bancshares |
| MDTA | Megadata Corporation |
| MDTV | M D U Communications International |
| MDURN | M D U Resource Group, Inc. |
| MDURP | M D U Resource Group, Inc. Preferred |
| MDWB | Midwest Savings Bank |
| MDWV | Medwave, Inc. |
| MDWY | Midway Airlines Corporation |
| MEAD | Meade Instrument Corporation |
| MEAN | Menacingly Evil Antagonistic Network |
| MECH | M E C H Financial, Inc. |
| MEDC | Med-Design Company |
| MEDI | Medimmune, Inc. |