legal wife of a high-ranking court official
Historical honorific term from the Heian period, referring specifically to the principal wife of a regent (sesshō or kampaku), imperial adviser, or Grand Council of State official. Not used in modern Japanese outside historical contexts.
Kita no Mandokoro was a term for the legal wife of a regent family.
Originally denoting the northern quarters of an aristocratic residence, where the principal wife lived; it subsequently became a title for the principal wife of a high-ranking courtier, especially a regent.