NK
- nK – (s) Nanokelvin
- NKA – No Known Allergies
- N/K/A – Now Known As
- NKVD – (i) Narodnyi Komissariat Vnutrennikh Del (Russian "People's Commissariat of Internal Affairs") (1934–1954)
Read more about this topic: List Of Acronyms And Initialisms: N
NK
Read more about this topic: List Of Acronyms And Initialisms: N