tetracyclo

The story

1. Proto-Indo-European*kʷetwóres
2. Proto-Hellenic*kʷétwores
3. Ancient Greekτέσσᾰρες (téssăres)
4. Ancient Greekτετρᾰ- (tetră-)
5. Englishtetra-
6. Late Latincyclus
7. Middle Englishcicle
8. Englishcycle
9. Ancient Greekκυκλῐκός (kuklĭkós)
10. Classical Latincyclicu
11. Middle Frenchcyclique
12. Frenchcyclique
13. Classical Latincyclicus
14. Englishcyclic
15. Englishcyclo-
16. English todaytetracyclo

From tetra- + cyclo-.