| M1 | mitral first [sound]; myeloblast; slight dullness |
|---|---|
| MAC | MacConkey [broth]; major ambulatory category; malignancy-associated changes; maximum allowable conce... |
| MAVR | mitral and aortic valve replacement |
| MC | mass casualties; mast cell; Master of Surgery [Lat. Magister Chirurgiae]; maximum concentration; Med... |
| Mc | mitral closure |