thyroepiglottic

The story

1. Proto-Indo-European*dʰwer-
2. Proto-Hellenic*tʰurā
3. Ancient Greekθῠ́ρᾱ (thŭ́rā)
4. Ancient Greekθῠρεός (thŭreós)
5. Proto-Indo-European*weyd-
6. Proto-Indo-European*wéydos
7. Proto-Hellenic*wéidos
8. Ancient Greekεἶδος (eîdos)
9. Ancient Greekθῠρεοειδής (thŭreoeidḗs)
10. New Latinthyreoīdēs
11. Englishthyroid
12. Englishthyro-
13. Proto-Indo-European*h₁ep-
14. Proto-Indo-European*h₁éps
15. Proto-Indo-European*h₁épi
16. Proto-Hellenic*epí
17. Ancient Greekἐπί (epí)
18. Ancient Greekἐπῐ- (epĭ-)
19. Proto-Hellenic*glṓt͏̌t͏̌ā
20. Ancient Greekγλῶσσᾰ (glôssă)
21. Ancient Greekγλωσσῐ́ς (glōssĭ́s)
22. Ancient Greekἐπῐγλωσσῐ́ς (epĭglōssĭ́s)
23. Ancient Greekἐπῐγλωττῐ́ς (epĭglōttĭ́s)
24. New Latinepiglōtti
25. Englishepiglottis
26. Englishepiglottic
27. English todaythyroepiglottic

From thyro- + epiglottic.