Where does “duo” come from?
duo (Middle High German) comes from Old High German dū, from Proto-West Germanic þū, from Proto-Germanic *þū, from Proto-Indo-European túh₂ — you, thou.
duo (Middle High German): then, at that time
Ancestry of “duo”, step by step
| Step | Language | Word | Meaning |
|---|
| 1 | Old High German | dū | — |
| 2 | Proto-West Germanic | þū | you |
| 3 | Proto-Germanic | *þū | — |
| 4 | Proto-Indo-European | túh₂ | you, thou |