alkylguanine

The story

1. Akkadian𒎎𒋆𒁉𒍣𒁕 (guḫlum)
2. Aramaicכוחלא (kuḥlā)
3. Arabicكُحْل (kuḥl)
4. Andalusian Arabicكُحُول (kuḥūl)
5. Medieval Latinalcoho
6. Middle Englishalcofol
7. Englishalc(ohol)
8. Proto-Indo-European*swel-der.?
9. Ancient Greekῡ̔́λη (hū́lē)
10. Englishalkyl
11. Quechuawan
12. Spanishguano
13. Englishguano
14. Englishguanine
15. English todayalkylguanine

From alkyl + guanine.