azetirelin

The story

1. Englishazetidine
2. Proto-Indo-European*dʰwer-
3. Proto-Hellenic*tʰurā
4. Ancient Greekθῠ́ρᾱ (thŭ́rā)
5. Ancient Greekθῠρεός (thŭreós)
6. Proto-Indo-European*weyd-
7. Proto-Indo-European*wéydos
8. Proto-Hellenic*wéidos
9. Ancient Greekεἶδος (eîdos)
10. Ancient Greekθῠρεοειδής (thŭreoeidḗs)
11. New Latinthyreoīdēs
12. Englishthyroid
13. Englishthyro-
14. Proto-Indo-European*trep-
15. Ancient Greekτρέπω (trépō)
16. Ancient Greekτροπή (tropḗ)
17. Ancient Greekτροπῐκός (tropĭkós)
18. Englishthyrotropin
19. Proto-Italic*wre-
20. Latinre-
21. Old Frenchre-
22. Proto-Indo-European*(s)leg-
23. Proto-Indo-European*(s)leg-s-ós
24. Latinlaxus
25. Latinlaxō
26. Vulgar Latin*laxicāre
27. Vulgar Latin*lassicāre
28. Old Frenchlaschier
29. Old Frenchrelaschier
30. Old Frenchrelaisser
31. Middle Englishrelesen
32. Englishrelease
33. English todayazetirelin

From aze(tidine) + -tirelin (“thyrotropin releasing hormone analog”).