bicyclo

The story

1. Proto-Indo-European*dwóh₁
2. Proto-Indo-European*dwi-
3. Proto-Italic*dwi-
4. Latinbi-
5. Englishbi-
6. Proto-Indo-European*kʷelh₁-redup.
7. Proto-Indo-European*kʷékʷlos
8. Proto-Hellenic*kʷókʷlos
9. Proto-Hellenic*kúklos
10. Ancient Greekκύκλος (kúklos)
11. Late Latincyclus
12. Middle Englishcicle
13. Englishcycle
14. Ancient Greekκύκλος (kúklos)
15. Ancient Greekκυκλῐκός (kuklĭkós)
16. Classical Latincyclicu
17. Middle Frenchcyclique
18. Frenchcyclique
19. Classical Latincyclicus
20. Englishcyclic
21. Englishcyclo-
22. English todaybicyclo

From bi- + cyclo-.