hypoautofluorescent

The story

1. Proto-Indo-European*upó
2. Ancient Greekῠ̔πό (hŭpó)
3. Ancient Greekὑπο- (hupo-)
4. Englishhypo-
5. Proto-Indo-European*h₂ew
6. Proto-Indo-European*tó-
7. Proto-Hellenic*autós
8. Proto-Indo-European*h₂ew
9. Ancient Greekαὖ (aû)
10. Ancient Greekτόν (tón)
11. Ancient Greekαὐτός (autós)
12. Ancient Greekαὐτο- (auto-)
13. Englishauto-
14. Proto-Indo-European*bʰel-
15. Proto-Indo-European*bʰlewH-
16. Proto-Indo-European*bʰluH-yé-ti?
17. Latinfluō
18. Latinfluor
19. Englishfluor
20. Englishfluorite
21. Middle Low Germanspar
22. Old Englishspærstān
23. Middle Englishsparston
24. Englishsparstonebf.
25. Englishspar
26. Englishfluorspar
27. Englishfluorescencebf.
28. Englishfluoresce
29. Englishfluorescent
30. Englishautofluorescent
31. English todayhypoautofluorescent

From hypo- + autofluorescent.