Where does “dau” come from?
dau (Old Irish) comes from Proto-Celtic dwau, from Proto-Brythonic dọw, from Proto-Celtic *duwo, from Proto-Indo-European dwóh₁ — two.
Ancestry of “dau”, step by step
| Step | Language | Word | Meaning |
|---|
| 1 | Proto-Celtic | dwau | two |
| 2 | Proto-Brythonic | dọw | two |
| 3 | Proto-Celtic | *duwo | — |
| 4 | Proto-Indo-European | dwóh₁ | two |