phenylethyl

The story

1. Proto-Indo-European*bʰeh₂-
2. Proto-Indo-European*bʰh₂nyéti
3. Proto-Hellenic*pʰáňňō
4. Ancient Greekφαίνω (phaínō)
5. Frenchphéno-
6. Proto-Indo-European*swel-der.?
7. Ancient Greekῡ̔́λη (hū́lē)
8. Frenchphényle
9. Englishphenyl
10. Proto-Indo-European*h₂eydʰ-
11. Proto-Hellenic*áitʰō
12. Ancient Greekαἴθω (aíthō)
13. Ancient Greekᾱ̓ήρ (āḗr)influ.?
14. Ancient Greekαἰθήρ (aithḗr)
15. Latinaethēr
16. GermanÄther
17. GermanEther
18. Ancient Greekῡ̔́λη (hū́lē)
19. GermanEthy
20. Englishethyl
21. English todayphenylethyl

From phenyl + ethyl.