chloralhydrate

The story

1. Proto-Indo-European*ǵʰelh₃-
2. Proto-Indo-European*ǵʰl̥h₃rós
3. Proto-Hellenic*kʰlōrós
4. Ancient Greekχλωρός (khlōrós)
5. Englishchlorine
6. Akkadian𒎎𒋆𒁉𒍣𒁕 (guḫlum)
7. Aramaicכוחלא (kuḥlā)
8. Arabicكُحْل (kuḥl)
9. Andalusian Arabicكُحُول (kuḥūl)
10. Medieval Latinalcoho
11. Middle Englishalcofol
12. Englishalcohol
13. Englishchloral
14. Proto-Indo-European*wed-
15. Proto-Indo-European*wódr̥
16. Proto-Hellenic*údōr
17. Ancient Greekῡ̆̔́δωρ (hū̆́dōr)
18. Ancient Greekὑδρο- (hudro-)
19. Frenchhydr-
20. Frenchhydrate
21. Englishhydrate
22. English todaychloralhydrate

From chloral + hydrate.