Where does “deu” come from?
deu (Middle Welsh) comes from Proto-Brythonic *dow, from Proto-Celtic *duwo, from Proto-Indo-European dwóh₁ — two.
Ancestry of “deu”, step by step
| Step | Language | Word | Meaning |
|---|
| 1 | Proto-Brythonic | *dow | — |
| 2 | Proto-Celtic | *duwo | — |
| 3 | Proto-Indo-European | dwóh₁ | two |