The story
- Proto-Indo-European*tréyes
- Proto-Indo-European*tri-
- Proto-Italic*tri-
- Latintri-
- Englishtri-
- Proto-Indo-European*h₂eǵ-?
- Proto-Indo-European*h₂eḱs-
- Proto-Italic*aksis
- Latinaxis
- Englishaxis
- Proto-Indo-European*h₂el-
- Proto-Indo-European*h₂élisder.?
- Englishaxial
- English todaytriaxial
Etymology from Wiktionary, CC BY-SA 4.0.