O-oku was a residential place in Edo-jo castle where the Tokugawa Shogun family's children, lawful wife and oku jochu (maids working in the domestic quarters of a shogun or feudal lords) (also called goten jochu [palace maids]) resided.
大奥（おおおく）とは江戸城に存在した徳川将軍家の子女や正室、奥女中（御殿女中）たちの居所。