| MSN | main sensory nucleus; Master of Science in Nursing; mildly subnormal |
|---|---|
| MVN | medial ventromedial nucleus |
| NA | Avogadro constant or number; nalidixic acid; Narcotics Anonymous; network administrator; neuraminida... |
| NARC | narcotic; National Association for Retarded Children; nucleus arcuatus |
| NGC | nucleus reticularis gigantocellularis |