postreperfusion

The story

1. Proto-Indo-European*pós
2. Proto-Indo-European*pósti
3. Proto-Italic*posti
4. Old Latinposte
5. Latinpost
6. Englishpost-
7. Proto-Italic*wre-
8. Latinre-
9. Old Frenchre-
10. Middle Englishre-
11. Englishre-
12. Proto-Indo-European*per-
13. Proto-Italic*peri-
14. Latinper-
15. Proto-Indo-European*ǵʰew-
16. Proto-Indo-European*ǵʰewd-
17. Proto-Indo-European*ǵʰunédti
18. Proto-Italic*hundō
19. Latinfundō
20. Latinperfundō
21. Latinperfūsiō
22. Middle Frenchperfusion
23. Englishperfusion
24. Englishreperfusion
25. English todaypostreperfusion

From post- + reperfusion.