unmechanical

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*megʰ-der.?
9. Ancient Greekμηχανή (mēkhanḗ)
10. Ancient Greekμηχανικός (mēkhanikós)
11. Latinmēchanicus
12. Old Frenchmecanique
13. Middle Englishmechanic
14. Proto-Indo-European*h₂el-
15. Proto-Indo-European*h₂élisder.?
16. Middle Englishmechanical
17. Englishmechanical
18. English todayunmechanical

From un- + mechanical.