| MRU | mass radiography unit; minimal reproductive unit |
|---|---|
| MS | Maffuci syndrome; maladjustment score; mandibular series; Marfan syndrome; Marie-Strumpell [syndrome... |
| MSDC | Mass Spectrometry Data Centre |
| m/z | mass-to-charge ratio |
| PAM | pancreatic acinar mass; penicillin aluminum monostearate; peptidylglycine alpha-amidating monooxygen... |