Where does “三后” come from?

三后 (Japanese) comes from Japanese 三, from Middle Chinese さん.

三后 (Japanese): the empress consort, the empress dowager and the grand empress dowager

Definitions

  1. the empress consort, the empress dowager and the grand empress dowager

Ancestry of “三后”, step by step

三后 traces back through two separate lines of ancestry.

via Japanese 三

StepLanguageWordMeaning
1Japanese三three, 3; third; three
2Middle Chineseさん—

via Japanese 后

StepLanguageWordMeaning
1Japanese后an empress; any other wife of a male aristocrat,...
2Middle Chineseこう—
Every word from Middle Chinese さん →Every word from Japanese 三 →