| mid-atlantic ridge | (n) a very long narrow elevation on the ocean floor that runs all the way from Iceland in the North Atlantic to Bouvet Island in the South Atlantic |
| mid-atlantic states | (n) a region of the eastern United States comprising New York and New Jersey and Pennsylvania and Delaware and Maryland |
| middle atlantic | (adj) of a region of the United States generally including Delaware; Maryland; Virginia; and usually New York; Pennsylvania; New Jersey, Syn. mid-Atlantic, Example: mid-Atlantic states |
