Ji 姬 was an ancestral name of the Zhou royal family, which later evolved to generally mean "lady" in successive eras. But there are no more detailed mentions on her family at Zhao (which was a Boyi-descent state and shared origins with Qin) except that it was "a prominent family."
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Her title should be distinguished from the other Empresses Dowager starting from Empress Lü. Those successors were granted the slightly different title which can be also translated as Empress Dowager (Chinese: 皇太后; pinyin: Huáng Tàihòu; Jyutping: Wong4 Taai3 hau6).
