| NEF | Notarzteinsatzfahrzeug (82) |
| neg | Negativ |
| NEJM | New England Journal of Medicine |
| NET | Normal-Effektivtemperatur |
| NET | Norethisteron |
| NF | Notfall |
| NG | Norgestrel |
| NGI | National Genomics Institute |
| NGM | Norgestimat |
| NHL | Non Hodgkin Lymphom |
| NHS | National Health Service |
| NI | Niereninsuffizienz |
| NIDDM | non insulin dependent diabetes mellitus |
| NIH | National Institutes of Health |
| nitts | noise induced temporary threshold shift |
| NIV | Nicht invasive Beatmung |
| NK | natürliche Killer (-zellen) |
| NL | nodus lymphaticus |
| NLG | Nervenleitgeschwindigkeit |
| NLKS | Nierenlagerklopfschmerz |
| NLM | U.S. National Library of Medicine |
| NM | Noduläres Melanom |
| nm | Nanometer |
| NMDA | n-Methyl-D-Aspartat |
| NMH | Niedermolekulares Heparin |
| NMM | noduläres malignes Melanom |
| NMN | Nicotinamidmononucleotid |
| NMR | Kernspintomographie (nuclear magnetic resonance) |
| N/ Nn | Nervus/ Nervi |
| Nn | Nervi |