neurosurgical

The story

1. Proto-Indo-European*(s)neh₁-
2. Proto-Indo-European*snéh₁wr̥
3. Ancient Greekνεῦρον (neûron)
4. Ancient Greekνευρο- (neuro-)
5. Englishneuro-
6. Proto-Indo-European*ǵʰes-
7. Proto-Indo-European*ǵʰésōr
8. Proto-Hellenic*kʰéhər
9. Ancient Greekχείρ (kheír)
10. Proto-Indo-European*werǵ-
11. Proto-Indo-European*worǵós
12. Proto-Hellenic*worgós
13. Ancient Greekχειρουργός (kheirourgós)
14. Ancient Greekχειρουργῐκός (kheirourgĭkós)
15. Late Latinchīrurgicus
16. Proto-Indo-European*h₂el-
17. Proto-Indo-European*h₂élisder.?
18. Medieval Latincirurgicālis
19. Middle Frenchcirurgica
20. Middle Englishcirurgical
21. Englishsurgical
22. English todayneurosurgical

From neuro- + surgical.