At the time when government posts were put into statutory form in the Nara Period, they kept their original meanings, but in the Heian Period, they started to represent high or low lineage as well and became symbols of Kakaku (family status), and lost the original meaning as government posts of Japan.
官職は奈良時代に法文化された当時はその本来の意味を有していたが、平安時代に入ると新しく血脈的な尊卑をも表現するようになり、ひいては家格の象徴となり、国家的な意味はほとんどなくなってしまう。