Where does “Matsudaira” come from?

Matsudaira (English) comes from Japanese 松平, from Japanese 平, from Middle Chinese 平.

Ancestry of “Matsudaira”, step by step

StepLanguageWordMeaning
1Japanese松平a placename, especially of a district in Toyota, Aichi Prefecture
2Japanese平something flat; flattened; something ordinary,...
3Middle Chinese平—
Every word from Middle Chinese 平 →Every word from Japanese 平 →Every word from Japanese 松平 →
Matsudaira — Etymology, Origin & Word History | Etymology Explorer