Where does “nerv” come from?

nerv (Czech) comes from Old Czech nerv, from Latin nervus, from Proto-Indo-European (s)new-.

nerv (Czech): nerve

Definitions

Step	Language	Word	Meaning
1	Old Czech	nerv	—
2	Latin	nervus	A sinew, tendon, nerve, muscle; A cord, string or...
3	Proto-Indo-European	(s)new-	—

nerv — Etymology, Origin & Word History | Etymology Explorer