| MNL | marked neutrophilic leukocytosis; maximum number of lamellae; mononuclear leukocyte |
|---|---|
| MPN | most probable number |
| NA | Avogadro constant or number; nalidixic acid; Narcotics Anonymous; network administrator; neuraminida... |
| Na | Avogadro number; sodium [Lat. natrium] |
| Nacq | number of acquisitions |