oversugar

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*ḱorkeh₂
8. Proto-Indo-Iranian*ćárkaraH
9. Proto-Indo-Aryan*śárkaraH
10. Sanskritशर्क॑रा (śárkarā)
11. Middle Persian𐭱𐭪𐭥 (šakar)
12. Arabicسُكَّر (sukkar)
13. Old Italianzucchero
14. Old Frenchçucre
15. Middle Englishsugre
16. Englishsugar
17. English todayoversugar

From over- + sugar (verb).