The story
- Ancient Greekκῆτος (kêtos)
- Latincētus
- Proto-Indo-European*swel-der.?
- Ancient Greekῡ̔́λη (hū́lē)
- Englishcet(yl)
- Proto-Indo-European*tréyes
- Proto-Indo-European*tri-
- Proto-Italic*tri-
- Latintri-
- Englishtri-
- Proto-Indo-European*médʰu
- Proto-Hellenic*métʰu
- Ancient Greekμέθυ (méthu)
- Ancient Greekῡ̔́λη (hū́lē)
- GermanMethy
- Englishmethyl
- Englishtrim(ethyl)
- New Latinammōnium
- Englishammonium
- Englishonium
- English todaycetrimonium
From cet(yl) + trim(ethyl) + -onium (“quaternary ammonium compound”).
Etymology from Wiktionary, CC BY-SA 4.0.