The story
- Proto-Indo-European*kʷetwóres
- Proto-Hellenic*kʷétwores
- Ancient Greekτέσσᾰρες (téssăres)
- Ancient Greekτετρᾰ- (tetră-)
- Englishtetra-
- Proto-Indo-European*ǵʰelh₃-
- Proto-Indo-European*ǵʰl̥h₃rós
- Proto-Hellenic*kʰlōrós
- Ancient Greekχλωρός (khlōrós)
- Englishchlor(ine)
- Proto-Indo-European*dʰeh₁-
- Englishchloride
- English todaytetrachloride
Etymology from Wiktionary, CC BY-SA 4.0.