overaccumulation

The story

1. Proto-Indo-European*úp
2. Proto-Indo-European*upér
3. Proto-Germanic*uber
4. Old Englishofer-
5. Middle Englishover-
6. Englishover-
7. Proto-Indo-European*h₂éd
8. Proto-Italic*ad
9. Proto-Italic*ad-
10. Latinad-
11. Proto-Indo-European*ḱewh₁-
12. Proto-Indo-European*ḱuh₁mósder.?
13. Latincumulus
14. Latincumulō
15. Latinaccumulō
16. Latinaccumulātiō
17. Middle Frenchaccumulation
18. Latinaccumulātiō
19. Middle Englishacumulacyon
20. Englishaccumulation
21. English todayoveraccumulation

From over- + accumulation.