unsurgical

The story

1. Proto-Indo-European*né
2. Proto-Indo-European*n̥-
3. Proto-Germanic*un-
4. Proto-West Germanic*un-
5. Old Englishun-
6. Middle Englishun-
7. Englishun-
8. Proto-Indo-European*ǵʰes-
9. Proto-Indo-European*ǵʰésōr
10. Proto-Hellenic*kʰéhər
11. Ancient Greekχείρ (kheír)
12. Proto-Indo-European*werǵ-
13. Proto-Indo-European*worǵós
14. Proto-Hellenic*worgós
15. Ancient Greekχειρουργός (kheirourgós)
16. Ancient Greekχειρουργῐκός (kheirourgĭkós)
17. Late Latinchīrurgicus
18. Proto-Indo-European*h₂el-
19. Proto-Indo-European*h₂élisder.?
20. Medieval Latincirurgicālis
21. Middle Frenchcirurgica
22. Middle Englishcirurgical
23. Englishsurgical
24. English todayunsurgical

From un- + surgical.