amphetamine

The story

1. Proto-Semitic*ʔalp-
2. Phoenician𐤀𐤋𐤐 (ʾlp)
3. Ancient Greekἄλφα (álpha)
4. Proto-Semitic*bayt-
5. Phoenician𐤁𐤕 (bt)
6. Ancient Greekβῆτᾰ (bêtă)
7. Ancient Greekἀλφάβητος (alphábētos)
8. Medieval Greekἀλφάβητον (alphábēton)
9. Classical Latinalphabētum
10. Middle Englishalphabete
11. Englishalphabet
12. Englishalpha-
13. Proto-Indo-European*médʰu
14. Proto-Hellenic*métʰu
15. Ancient Greekμέθυ (méthu)
16. Proto-Indo-European*swel-der.?
17. Ancient Greekῡ̔́λη (hū́lē)
18. GermanMethy
19. Englishmethyl
20. Proto-Indo-European*bʰeh₂-
21. Proto-Indo-European*bʰh₂nyéti
22. Proto-Hellenic*pʰáňňō
23. Ancient Greekφαίνω (phaínō)
24. Frenchphéno-
25. Ancient Greekῡ̔́λη (hū́lē)
26. Frenchphényle
27. Englishphenyl
28. Englishpheno-
29. Englishphen-
30. Proto-Indo-European*h₂eydʰ-
31. Proto-Hellenic*áitʰō
32. Ancient Greekαἴθω (aíthō)
33. Ancient Greekᾱ̓ήρ (āḗr)influ.?
34. Ancient Greekαἰθήρ (aithḗr)
35. Latinaethēr
36. GermanÄther
37. GermanEther
38. GermanEthy
39. Englishethyl
40. Egyptianjmn
41. Ancient GreekᾸ̓́μμων (Ắmmōn)
42. LatinAmmōn
43. Latinammoniacus
44. Englishammonia
45. Englishamine
46. Englishethylamine
47. Englishphenethylamine
48. Englishmethylphenethylamine
49. Englishalpha-methylphenethylamine
50. English todayamphetamine

Shortened form of a(lpha-)m(ethyl)ph(en)et(hyl)amine.