nonmechanical

The story

1. Proto-Indo-European*né
2. Proto-Germanic*ne
3. Proto-Indo-European*ís?
4. Proto-Indo-European*h₁óynos
5. Proto-Germanic*ainaz
6. Proto-Germanic*nainaz
7. Proto-West Germanic*nain
8. Old Englishnān
9. Middle Englishnon
10. Old Englishnān
11. Old Englishnān-
12. Middle Englishnon-
13. Englishnon-
14. Proto-Indo-European*megʰ-der.?
15. Ancient Greekμηχανή (mēkhanḗ)
16. Ancient Greekμηχανικός (mēkhanikós)
17. Latinmēchanicus
18. Old Frenchmecanique
19. Middle Englishmechanic
20. Proto-Indo-European*h₂el-
21. Proto-Indo-European*h₂élisder.?
22. Middle Englishmechanical
23. Englishmechanical
24. English todaynonmechanical

From non- + mechanical.