also: いんちょう
noun
office of a retired emperor
Historical term referring to the administrative office of a retired emperor (上皇) in the Heian period and later. Used in contexts discussing Japanese court history.
院庁は、上皇の政務を補佐する機関だった。
The In-no-chō was an organ that assisted the retired emperor in governmental affairs.
白河上皇は院庁を通じて政治を行った。
Retired Emperor Shirakawa conducted politics through the In-no-chō.
Explicit spelling with の, making the reading いんのちょう unambiguous.
院政 refers to the system of rule by a retired emperor, while 院庁 is the specific administrative office that supported that rule.
Compound of 院 (in, 'retired emperor') and 庁 (chō, 'government office'). The reading いんのちょう reflects the historical possessive particle の, while いんちょう is a contracted reading.