imperial edict conferring nobility titles (ancient China)
Historical term referring to a specific practice in ancient China; not used in modern Japanese contexts.
In ancient China, the emperor granted an imperial edict to confer a title of nobility upon a meritorious retainer.
imperial investiture of a vassal lord (ancient China); document conferring peerage
imperial investiture; installation (of a monarch)
The kanji 冊 originally referred to bamboo or wooden slips bound together to form a book, and by extension came to denote an official document or edict. The specific use for an imperial edict conferring nobility titles is a historical Chinese usage.