| MAR | main admissions room; marasmus; marrow; maximal aggregation ratio; medication administration record;... |
|---|---|
| MCx | main circumflex [artery] |
| MD | Doctor of Medicine [Lat. Medicinae Doctor]; magnesium deficiency; main duct; maintenance dose; major... |
| MPD | main pancreatic duct; maximum permissible dose; mean population doubling; membrane potential differe... |
| MPV | main portal vein; mean platelet volume; mitral valve prolapse |