Where does “duo” come from?

duo (Old High German) comes from Proto-Germanic þō, from Proto-Germanic sa, from Proto-Indo-European só — this; that.

duo (Old High German): then

Definitions

  1. then

Ancestry of “duo”, step by step

StepLanguageWordMeaning
1Proto-Germanicþōthey, those
2Proto-Germanicsathat
3Proto-Indo-Europeansóthis; that
Every word from Proto-Indo-European só →Every word from Proto-Germanic sa →Every word from Proto-Germanic þō →