NK

Lit; NahKampfkanone [CH]
Found on http://www.jedsite.info/index.html

NK

Type: Abbreviation Definitions: 1. Abbreviation for natural killer cells, under cell.
Found on http://www.medilexicon.com/medicaldictionary.php?t=60564

NK

New Kingdom
Found on http://www.reshafim.org.il/ad/egypt/glossary.htm

nk

no kidding
Found on http://www.noslang.com/dictionary/n/
No exact match found