cardiosurgical

The story

1. Proto-Indo-European*ḱerd-
2. Proto-Indo-European*ḱḗr
3. Proto-Indo-European*ḱr̥díyeh₂
4. Proto-Hellenic*kərdíyā
5. Ancient Greekκαρδία (kardía)
6. Englishcardio-
7. Proto-Indo-European*ǵʰes-
8. Proto-Indo-European*ǵʰésōr
9. Proto-Hellenic*kʰéhər
10. Ancient Greekχείρ (kheír)
11. Proto-Indo-European*werǵ-
12. Proto-Indo-European*worǵós
13. Proto-Hellenic*worgós
14. Ancient Greekχειρουργός (kheirourgós)
15. Ancient Greekχειρουργῐκός (kheirourgĭkós)
16. Late Latinchīrurgicus
17. Proto-Indo-European*h₂el-
18. Proto-Indo-European*h₂élisder.?
19. Medieval Latincirurgicālis
20. Middle Frenchcirurgica
21. Middle Englishcirurgical
22. Englishsurgical
23. English todaycardiosurgical

From cardio- + surgical.