Where does “nei” come from?

nei (Middle English) comes from Old Norse nei, from Proto-Germanic nai, from Proto-Indo-European né — not; no.

Ancestry of “nei”, step by step

StepLanguageWordMeaning
1Old Norseneino
2Proto-Germanicnainever
3Proto-Indo-Europeannénot; no
Every word from Proto-Indo-European né →Every word from Proto-Germanic nai →Every word from Old Norse nei →
nei — Etymology, Origin & Word History | Etymology Explorer