| M.M. | Multiple Myeloma |
|---|---|
| M.O. | medulla oblongata |
| M.O.D. | Mean Optical Density |
| M.P.D. | Multiple Personality Disorder |
| M.R.C. | Medical Research Council |
| M.R.S. | Melkersson-Rosenthal syndrome |
| M.V.C. | Maximum Voluntary Isometric Contraction |
| M.W.D. | Maximum Walking Distance |
| M.Z. | mantle zone |