MD3, MD 3 or MD-3 can mean:
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Dätwyler MD-3 Swiss Trainer, a Swiss light aircraft
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Flyitalia MD3 Rider, an Italian ultralight aircraft
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Maryland's 3rd congressional district
Maryland's 3rd congressional district covers all of Howard County, Maryland, Howard county as well as parts of Anne Arundel County, Maryland, Anne Arundel and Carroll County, Maryland, Carroll counties. The seat is currently represented by Sarah ...
, a United States electoral region
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Maryland Route 3, a United States highway
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MD3 (file format)
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