Where does “Donau” come from?

Donau (Danish) comes from German Donau, from German Donaw, from German Tonaw, from Middle High German Tuonawe.

Ancestry of “Donau”, step by step

StepLanguageWordMeaning
1GermanDonauDanube
2GermanDonaw—
3GermanTonaw—
4Middle High GermanTuonawe—
Every word from Middle High German Tuonawe →Every word from German Tonaw →Every word from German Donaw →
Donau — Etymology, Origin & Word History | Etymology Explorer