magnetobacterial

The story

1. Ancient GreekΜάγνης (Mágnēs)
2. Ancient Greekμᾰ́γνης (mắgnēs)
3. Old Frenchmagnete
4. Ancient Greekμᾰ́γνης (mắgnēs)
5. Latinmagnēs
6. Middle Englishmagnete
7. Englishmagnet
8. Englishmagnet-
9. Englishmagneto-
10. Ancient Greekβακτηρία (baktēría)
11. Ancient Greekβακτήριον (baktḗrion)
12. New Latinbactēria
13. Englishbacteria
14. Proto-Indo-European*h₂el-
15. Proto-Indo-European*h₂élisder.?
16. Englishbacterial
17. English todaymagnetobacterial

From magneto- + bacterial.