rhizocompartmental

The story

1. Proto-Indo-European*wréh₂ds
2. Ancient Greekῥῐ́ζᾰ (rhĭ́ză)
3. Englishrhizo-
4. Proto-Indo-European*ḱe?
5. Proto-Indo-European*ḱóm
6. Proto-Italic*kom
7. Proto-Italic*kom-
8. Latincom-
9. Proto-Indo-European*perh₃-
10. Proto-Indo-European*pérh₃tis?
11. Proto-Italic*partis
12. Latinpars
13. Latinpartiō
14. Latinpartior
15. Latincompartīrī
16. Italiancompartire
17. Italiancompartimento
18. Middle Frenchcompartiment
19. Englishcompartment
20. Proto-Indo-European*h₂el-
21. Proto-Indo-European*h₂élisder.?
22. Englishcompartmental
23. English todayrhizocompartmental

From rhizo- + compartmental.